DESIGNING WITH BIO-BASED BUILDING MATERIALS

– CHALLENGES AND OPPORTUNITIES - Madrid, Spain – 24th & 25th February 2016

COST ACTION FP1303 PERFORMANCE OF BIO-BASED BUILDING MATERIALSBOOK OF ABSTRACT FROM JOINT TECHNICAL WORKSHOP

DESIGNING WITH BIO-BASED BUILDING MATERIALS

– CHALLENGES AND OPPORTUNITIES - Fourth COST Action FP1303 International Conference

Madrid, Spain – 24th & 25th February 2016

BOOK OF ABSTRACT

EDITORS:TERESA DE TROYA, JORGE GALVÁN AND DENNIS JONES

National Institute for Agricultural and Food Research and Technology (INIA) and “Eduardo Torroja” Institute for Construction Sciences (IETcc-CSIC)

Madrid, 2016

COST ACTION FP1303 PERFORMANCE OF BIO-BASED BUILDING MATERIALS

Book of abstract of the 4th FP1303 International Conference Designing with bio-based building materials – Challenges and opportunities

Editors: Teresa de Troya, Jorge Galván and Dennis Jones

Editorial office: SP Technical Research Institute of Sweden. Box 857, 501 15 Borås, Sweden (headquarters)

Organizers: Teresa de Troya, National Institute for Agricultural and Food Research and Technology (INIA) and Jorge Galván “Eduardo Torroja” Institute for Construction Sciences (IETcc-CSIC).

Disclaimer: This book of abstracts compiles the papers and posters presented at the 4th FP1303 International Conference “Designing with bio-based building materials – Challenges and opportunities” held in Madrid, Spain on 24 -25 February 2016. The opinions expressed within are hose of the authors and may not necessarily represent those of the host, the editors or the respective COST Actions.

All the papers have been reviewed.

Cover photo

Metropol Parasol (Sevilla)

Metropol Parasol, known as the Mushrooms, is the largest wood structure of the world, has 2 columns of concrete which incorporate elevators to access to the belvedere, it is located in the “Plaza de la Encarnación” in Seville (Spain). Its dimensions are 150 x 70 meters, and 26 meters of height. The winning project was opened by the Seville City Council to carry out the rehabilitation of the square. Its designer was the Berliner architect Jürgen Mayer.

The construction began on June 26, 2005, at an estimated cost of 50 million euros, after having raised the cost of the project, it was inaugurated on March 27, 2011.

In the first phase of the project, in June 2005, it came to light that the construction of the complex structure of Parasol, such as it was designed was not technically viable, after modifying the structure of umbrellas replacing the metal by timber and increasing the budget in 8 million, the works continued. The structure was inaugurated in 2011 with an impact on international media, like the British newspaper The Guardian.

In January 2013, the space Metropol Parasol was chosen among 335 candidate projects, as one of five finalists of the European Union Prize for Contemporary Architecture, awarded biannually to the European Union and the Mies Van Der Rohe Foundation.

Acknowledgement

Dr. Queipo de Llano for his contribution to this action, particularly by the inspiring drawing of the cover, and Luis Miguel Jimenez for his help organizing this event.

SP Report 2016:10

ISBN 978-91-88349-16-3

SP© Technical Research Institute of Sweden.

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• Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

• Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

• New forms of architecture for the 21st century using bio-based materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9Peter Wilson

• Advances and handicaps of using wood-based materials in construction in Spain: an overview . . . . . . . . . . . . . . . . . . . . . 11Luis Vega, Juan Queipo de Llano, Carlos Villagrá

• Identification Methods of Biobased Surface Finishes on Antique Wooden Parquets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Anna Rozanska, Anna Sandak

• Properties of sandwich panels produced from MDF and thermally compressed veneres . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Ümit Büyüksarı, Salim Hiziroglu, Hüseyin Akkılıç, Nadir Ayrılmış

• Possibilities of utilisation polyethylene terephthalate recycling in particleboard production -mould test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Ján Iždinský, Jozef Kúdela, Zuzana Vidholdová, Ladislav Reinprecht, Viktor Tóth

• Impact of Wood Preservative Treatments on Mechanical Properties of E-glass/PhenolicComposite (FRP ) Reinforcement for Laminated Wood Beams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Cihat Tascioglu, Barry Goodell, Roberto Lopez-Anido

• Mechanical properties of bio-based foam in ultralight particleboards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Martin Rhême, Ali Shalbafan, Heiko Thoemen

• Purpose-designed bio-composite platesfor the building sector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Michael Dorn, Thomas Bader

• Morphological changes of wood after short term natural weathering evaluated with SEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25Anna Sandak, Jakub Sandak, Marion Noël, Solène Barbotin

• Natural materials used as a reinforcement of lumber . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Izabela Burawska

• Characteristic timber damage in cultural monuments of Kosovo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29Agron Bajraktari, Florit Hoxha, Rrahim Sejdiu

• Leaching effect of rain in outdoor wooden applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31Laszlo Tolvaj, Robert Nemeth, Denes Varga

• Design and durability of traditional wooden houses. A case study . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33Maria-Cristina Popescu, Carmen-Mihaela Popescu

• Comparison of a new and a 40 years old robinia glued-laminated load bearing element . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35József Ábrahám, Norbert Horváth, Csilla Csiha, Róbert Németh, Miklós Bak

• Effect of sawing pattern and species on the permeability to water of two conifers: radiata and Scots pine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37Fernández-Golfin, J.I.; Galvan, J.; Conde, M.; Conde, M.

• Hydro-mechanical behaviour of Aucoumea klaineana under drying process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39Samuel Ikogou, Rostand Moutou Pitti, Serge Ekomy Ango

• The impacts of the construction and surrounding conditions on biodeterioration of wooden windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41Zuzana Vidholdová, Ladislav Reinprecht, Stanislav Jochim, Ján Iždinský

• WoodBuild – key results and thoughts for future work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43Jöran Jermer

• The challenge of building with biobased materials in termite áreas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45Lina Nunes, Sónia Duarte

• Formation of cracks in wooden elements – design, moisture and durability aspects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47Linda Meyer-Veltrup, Christian Brischke, Christian Goritzka, Ulrich Hundhausen

TABLE OF CONTENTS

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• The problem of exterior structures built in Northern Spain climatesin Fir and Spruce due wood destroying fungi attacks. The example of a wood exterior structure in Pontevedra, Spain and the importance of design in the performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 David Lorenzo, Juan Fernández, Manuel Touza, Manuel Guaita, Alfonso Lozano, Josu Benito,Teresa de Troya

• Interior designing with the surface Decorative Veneers Made of Black locust (Robinia pseudoaccacia L.) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51Roman Réh

• Performance of windows made of thermally and non-modified norway spruce (picea abies l.) in different climatic conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55Aleš Ugovšek, Barbara Šubic, Gregor Rep, Miha Humar, Boštjan Lesar, Nejc Thaler, Christian Brischke, Dennis Jones, José Ignacio Lozano

• Durability is in details - example of a recently installed timber cladding in Zagreb . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57Vjekoslav Živković, Hrvoje Turkulin

• Performance of a new bio-based insulation board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59Palumbo M, Lacasta AM

• Influence of the retention and penetration of Cu based preservatives on the performance of softwoods in ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61Miha Humar, Boštjan Lesar, Nejc Thaler, Davor Kržišnik, Mojca Žlahtič

• Methodological approach to the evaluation of the CLT for use in service class 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63Galván, J., Troya, T., Oteiza, I., Martinez, E., Fernández-Golfin, J.I.

• Hygrothermal performance of cross laminated timber as external wall layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65Villu Kukk, Jaan Kers

• A wireless system for monitoring the internal temperature and humidity values of different types of wood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67S. Aparicio, J. Galván, M.G. Hernández, J.I. Fernandez-Golfin, J.J. Anaya

• Sustainability indicators set for agricultural residues based panels in developing countries . . . . . . . . . . . . . . . . . . . . . . . . . . . 69Christelle Ganne-Chédeville, Raphael Maineiro, Jan Grenz, Ueli Jezler

• BIO4ever project concept to promote the bio-based materials in modern construction sector . . . . . . . . . . . . . . . . . . . . . . . 71Anna Sandak, Jakub Sandak, Bruno Simões, Federico Prandi, Raffaele Dei Amicis

• Use of Bio-based Building Materials in Turkey-Present situation and future challenges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73Nurgul Tankut, Eser Sozen

• Austrian wood designer buildings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75Martin Weigl, Michael Truskaller, Martin Teibinger, Franz Dolezal

• Challenges and opportunitiesof the wood constructionsector – insights from the InnoRenew CoE market analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77Matthew Schwarzkopf, Michael Burnard, Amy Simmons, Črtomir Tavzes, Andreja Kutnar

• REE DCOB - An eco - efficient building technology for monolithic walls based on earth and reeds . . . . . . . . . . . . . . . 79Paulina Faria, Paulo Carneiro, Alina Jerónimo, Davide Malheiro

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Welcome to the fourth conference in COST Action FP1303 ”Designing with bio-based building materials – Challenges and opportunities”. This conference, held at Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA) in Madrid, Spain on 24-25 February 2016 continues the strong theme of collaboration and research and development in the use of bio-based materials within this COST Action.

The interest in scientists and in particular Early Career Investigators (ECIs) attending this Action through its meetings, training schools and Short Term Scientific Missions is testament to the importance in developing bio-based building solutions meeting modern needs. This work combines the need to select the correct material in a particular use, apply the correct design and undertake necessary maintenance to ensure the longevity of a product. The combination of all these factors is the theme for this meeting, and it is expected that delegates will be able to develop a range of collaborative activities following the range of stimulating presentations to be given during the two days. We are fortunate to have three keynote presentations, looking respectively at architectural requirements, the use of biobased materials in Spain and performance criteria for materials from a recently completed European project.

COST FP1303 has been active at a range of events recently, with joint sessions with the 8th European Conference on Wood Modification, held in Helsinki, Finland and the International panel Products Symposium, held in Llandudno, UK. The latter conference provided an excellent forum for non-wood building products, as well as providing strong links to European industries.

For any meeting to be successful, it is essential to have a good team working together. I wish to express my sincere gratitude to the local organisers and scientific committee for their help and advice in making this meeting a reality. In addition, a meeting is judged on the quality of the presentations given and I wish to thank all those who submitted the abstracts within this book. Just by looking at the agenda and reading the abstracts, it is obvious we will have two intensive days covering a wide range of topics, accompanied by many discussions.

I wish to welcome everyone to Madrid and hope you all have two interesting and scientifically stimulating days!

Dennis Jones Chair, COST FP1303

PREFACE

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Wood has been traditionally in construction in Spain since the beginning of history as in Europe. Housing stock including private housing and historical buildings which comprises our artistic and cultural legacy constructed before the 1920s have timber as part of their structure. The warm climatic conditions of Spain, allow the development of wood decay organisms, of which not all are present in other European Countries.

In the last decades the use of renewable materials has been driven forward so as to counteract environmental impacts. In this sense wood is a renewable bio-based building material resource.

The national policy within the construction sector is directed towards the conservation and rehabilitation of existing housing stock including historical buildings. In this sense the Ministry involved in this area launched a few years ago a strategic plan to properly resolve the damages produced in buildings covering all building materials, including timber. This policy brings Spain into line with the European objectives, which include the reduction in 20% of greenhouse gases and a 20% increase in the use of renewable materials.

The Spanish regulations in construction are set out in the Technical Building Code, and in particular the “DB SE M Structural Safety: Timber structures” where are explained all the specifications for wood. Since many years ago, the architects use these tools when timer is used in construction, but still, there are markets gaps that need to be solved.

The participation of Spain in this COST FP1303 “Designing with bio-based wooden material” gives the opportunity to help to develop this challenge.

As local organizers we would like to thank all of the Centers and Companies involved in this common project.

Teresa de Troya Jorge GalvánLocal organizers

FOREWORD

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NEW FORMS OF ARCHITECTURE FOR THE 21ST CENTURY USING BIO-BASED MATERIALSPeter Wilson

Architect and Managing Director.

Timber Design Initiatives Ltd, 90 Constitution Street, Edinburgh, EH8 8JJ, Scotland.

timberdesigninitiatives@gmail.com

KEYWORDSArchitecture, Timber, Solid Timber

With changing perceptions about global warming and the need to protect the environment from future irresponsible plunder of the earth’s irreplaceable natural resources, architects, engineers and other construction professionals are increasingly receptive to the design and manufacturing opportunities presented by bio-based materials and the role of wood-based architecture as a form of climate protection (1). This process, whilst ongoing, is still relatively slow and far from universal, however, and a result, arguably, of inadequate knowledge of these materials and their properties as well as insufficient training in their use and construction potential.

There are of course many other issues affecting widespread take-up of bio-based materials by this sector of the global economy - poor supply chains, inadequate or non-existent certification, variable quality (and accuracy) of technical information, exchange rate variation and lack of understanding of end-use customer’ requirements (and prejudices) - being but a few of the additional challenges facing the committed specifier of bio-based materials.

Yet, even in the face of these obstacles, considerable design innovation has taken place in recent years in the use of bio-based products in construction (2), with a number of international architects and engineers acting as enthusiastic trailblazers in the development of new building types and construction components and systems made principally from wood but also from hemp, lime, straw and other naturally occurring materials.

Most influential amongst these innovations to date has been the development of new engineered wood products together with the increasing emergence of economically viable wood modification processes. The former (in laminated solid panel form (2)) has given rise to the achievement of ever-taller timber structures - principally to provide new forms of housing in densely urbanised settings - whilst the latter has given renewed impetus to the use of wood products in situations requiring high levels of durability.

Other factors have advanced the case for bio-based materials in the global construction industry, such as:

· increased demand for renewable building products; · potential to use bio-based materials in the manufacture of dimensionally stable products;· ability to utilise bio-based materials in offsite manufacture / prefabrication processes;· lighter weight of many bio-based construction components and consequent lighter weight of foundations;

· speed and quietness of erection of bio-based construction components (especially in urban areas);· precision manufacturing and assembly and consequent improvements in airtightness and thermal control in buildings;

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· ever-higher standards for internal air quality and thermal efficiency; · advances in fire control engineering and technology; · potential for local manufacturing and consequent sustainability of rural economies; · the use of indigenous materials to deliver regional architectural distinction (4)

To date, many projects have been completed around the world that effectively illustrate these and other qualities of bio-based materials and products and their relative performance in different climatic zones. Other projects - such as Expos - provide the opportunity to test new ideas and new technologies that are based on the continuing research and development taking place on a wide range of bio-based materials, whilst a range of innovative construction programmes and design competitions offer possibilities for young architects and engineers to gain knowledge and experience in the use of bio-based materials and products.

That said, the various areas of research and development on bio-based materials taking place in research institutes and higher education establishments around the globe are arguably insufficiently coordinated with - or responsive to - the applied research and development taking place in the construction industry itself, and vice versa: a situation that needs to change if universal preferencing of bio-based materials is to take place in the construction of new or extended cities in the next decades of the 21st century. Positive alteration of political and public perceptions of bio-based materials as well as the regulatory changes and industry transformation required to ensure greater take-up of these renewable materials and products will only come about through collaborative action on the part of academia and industry. Real innovation does not happen in isolation and this paper / presentation aims - through an exploration of recent and possible future developments in research, design, manufacturing and construction - to identify the linkages between each of these areas necessary to enable greater and speedier take-up in the use of bio-based materials in the global built environment.

REFERENCES1 Kaufmann H., Nerdinger W., 2012. Building with Timber - Paths into the Future. Munich, Prestel Verlag.

2 Mayo J., 2015. Solid Wood - Case Studies in Mass Timber Architecture, Technology and Design. London, New York, Routledge.

3 Bernheimer A., Ed. 2014. Timber in the City - Design and Construction in Mass Timber. New York. Oro Editions.

4 Lefaivre L., Tzonis A., 2003. Critical Regionalism - Architecture and Identity in a Globalised World. Munich, Berlin, London, New York, Prestel Verlag.

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ADVANCES AND HANDICAPS OF USING WOOD-BASED MATERIALS IN CONSTRUCTION IN SPAIN: AN OVERVIEW Luis Vega1, Juan Queipo de Llano2, Carlos Villagrá2

1Ministry of Public Works and Transport. Paseo de la Castellana, 67. 28071 Madrid, Spain.2Eduardo Torroja Institute for Construction Science – CSIC. Serrano Galvache, 4. 28033 Madrid, Spain.

1lvega@fomento.es,2jqueipo@ietcc.csic.es,2carlosv@ietcc.csic.es

KEYWORDSWood construction, timber, regulations, design, building

Wood can be considered the first construction material, and therefore a traditional material. However, thanks to new advances today we can find highly technological wood-based products that can compete with, or even surpass (regarding sustainability, for example), other present materials.

Nevertheless, concerning life cycle analysis, even if wood seems to be the most sustainable material, many issues have to be taken into account. A key factor in assessing sustainability of a construction material is its fitness for purpose and working life. In these aspects, wood-based materials have to make a bigger research effort.

Photo 1: Evaluation of functional behaviour of solid wood in outdoor above ground applications

Photo 2: Evaluation of functional behaviour of solid wood panel in outdoor above ground applications

Fitness for purpose and working life are closely related to a right design. The design has to consider climate conditions, which were a very important factor in vernacular architecture, but today’s globalization unfortunately has forgotten about. Extend the life of wood based products by means of a right design is a fundamental aspect that is gaining importance in research fields. As an example, some undergoing projects in Spain covering this aspects are the National project BIA-42434R on the Evaluation of functional behaviour of wood in outdoor above ground applications, or the project called Sustainability and durability of wood structures, the case of CLT on exterior bearing walls.

Another essential issue when talking about wood construction in Spain is its regulation framework. In Spain we have gone through periods where wood construction was forbidden in social housing, or through times in

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the eighties where there was an almost absolute lack of regulations about this material. Today, as a result of the alignment with the Eurocodes, Spanish Building Code and a set of standards place wood-based materials at the same level that all others.

But we must not forget that this irregular development of wood regulations in the past has resulted in a low use of this material by designers, linked to a low level of knowledge of it. Our present regulation is finally quite complete, but it is necessary to keep making efforts in training good professionals.

Photo 3: Representative example of timber construction

REFERENCESEN 1995-1-1 (2004): Eurocode 5: Design of timber structures - Part 1-1: General - Common rules and rules for buildings. The European Union Per Regulation 305/2011, Directive 98/34/EC, Directive 2004/18/EC.

Real Decreto 314/2006, Spanish Building Code. Ministry of Housing. Madrid. March 2006.

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IDENTIFICATION METHODS OF BIOBASED SURFACE FINISHES ON ANTIQUE WOODEN PARQUETS Anna Rozanska1*, Anna Sandak2

1Wood Science Department of the Warsaw University of Life Sciences (SGGW) 2CNR-IVALSA Trees and Timber Institute

*annamaria.rozanska@gmail.com

KEYWORDSwood, method, durability

Traditional methods of wood impregnation consisted in soaking it with substances of natural origin: vegetable oils, beet sugar, cane sugar, paraffin, colophony, waxes, potassium alum, etc. Since the 19th century, the method of impregnation with coal-tar creosote was being developed. Other substances used in this kind of applications are water soluble compounds such as mercury chloride, zinc chloride, copper sulfate and later, salt mixtures.

Nowadays, linseed varnish has been replaced with mostly synthetic parquet oils that are applied cold, and whose surface is additionally covered with wax oil.

Due to environmental concerns, biobased surface finishes are growing in popularity once more, and at the same time they are high quality products.

The choice of finishing materials determines the durability and specific properties of wood surface, both aesthetic ones as colour, gloss or roughness, as the ones related mostly to resistance, such as hardness, resistance to abrasion or resistance to scratches [Rozanska et al. 2012, 2013].

Correct identification of surface finishes used in a given antique parquet is crucial for the planned conservation works, because the kind of surface finish has a major influence on its visual and resistance properties.

Antique floor surface finish identification with non-destructive methods is a complex process and requires further research.

Fig. 1. Water contact angle on the front side of antique wood, antique wood after polishing, contemporary wood without finish and contemporary wood covered with wax and varnish

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In density profile tests, the biggest density value is observedon the front side, which is probably due to the presence of non-structural substances. Additionally, bigger values of contact angle (from 13 to 42%) of the original front surface of antique parquets (Fig.1) suggest that the parquets were soaked with oil or wax finishes (salts increase wood wettability). Moreover, qualitative and quantitative element content determined with XRF X-ray spectrofluorimetry focusing on the elements whose content in wood is high, such as potassium or calcium, as well as those elements, whose content is very low (Cl, Fe, Zn, Mg, Cu), shows that samples were soaked in lime (that was often used to protect wood), as well as chlorine, iodine, scandium and tin compounds.

Undoubtedly, the comparison of surface energy of the original front surface of antique wood (not treated) and the same surface after polishing, shows that in all the cases this value is higher for original parquet surfaces (Fig.2).

Fig. 2. Surface energy of the front side of antique wood, antique wood after polishing, contemporary wood without finish and contemporary wood covered with wax and varnish

It has also been proved that FT-NIR is an efficient tool for identifying freshly applied coatings of biobased finish on contemporary wood [Rozanska, Sandak 2013]. It is difficult to identify finish coatings on antique wood, because over the centuries antique buildings were often not maintained properly, they were intensely used and the parquets became worn and sometimes flooded with water due to leaking roofs and improper rainwater drainage systems that did not drive water sufficiently far away from building walls. This aspect was taken into account in our tests, which is why we took samples from external room corners - sampling point no. 1; from traffic paths - sampling point no. 2; and from internal room corners - sampling point no. 3; which permitted to prove that test results differed according to wood surface usage conditions. In such variable conditions, the original surface finishes could have been partially or completely worn out or washed away. Another process that influences the chemical composition of a surface is natural wood ageing. Moreover, it is possible that several different kinds of surface finish were applied to parquets during their long history (at first - varnish, and then - wax).

REFERENCESRóżańska A., Koryciński W., Auriga R., Beer P., 2012: Characteristics of the properties of traditional finishing coatings used to protect wood in antique parquets considering the possibility of their application in buildings under reconstruction, Annals of WULS- SGGW 80: 22-28.

Różańska A., Kowaluk G.,  Koryciński W., Beer P., 2013: Influence of wooden floor surface finish on its hardness, resistance to abrasion and resistance to scratches, Annals of WULS- SGGW 84: 97-115.

Rozanska, Sandak, 2013: Application of FT-NIR recognition of substances used for conservation of wooden parquets of 19th century manor house located in South-Eastern Poland, Proc. COST FP0904 & FP1006 International Workshop Characterization of modified wood in relation to wood bonding and coating performance”, 16-18 October, Rogla Slovenia.

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PROPERTIES OF SANDWICH PANELS PRODUCED FROM MDF AND THERMALLY COMPRESSED VENEERSÜmit Büyüksarı*, Salim Hiziroglu, Hüseyin Akkılıç, Nadir Ayrılmış

The objective of study is to evaluate some of the physical and mechanical properties of medium density fiberboard (MDF) panels laminated with veneer sheets compressed at different levels of pressure and temperatures. Rotary peeled veneer samples of European beech (Fagus orientalis Lipsky) were compressed at temperature levels of 150 oC, 180 oC, and 200 oC using 4 MPa and 6 MPa pressure for 8 min. Commercially produced MDF samples were laminated with such compressed veneer sheets.

Both modulus of elasticity (MOE) and modulus of rupture (MOR) of the specimens increased with increasing pressure and press temperature. Bending characteristics of the samples tested parallel to grain orientation resulted in significantly higher values than those of perpendicular grain to orientation for each manufacturing parameter. Thickness swelling of the samples was also influenced by increased pressure but variation in press temperature did not resulted in any influence on their dimensional stability.

The findings of this work could provide some potential to produce sandwich type panels with improved properties. It appears that initial data found in this study could be used to manufacture laminated panels with a fixed rate of adhesive but controlling press parameters as function of magnitude of pressure and temperature

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POSSIBILITIES OF UTILISATION POLYETHYLENE TEREPHTHALATE RECYCLING IN PARTICLEBOARD PRODUCTION - MOULD TESTJán Iždinský1a, Jozef Kúdela1b, Zuzana Vidholdová1c, Ladislav Reinprecht1d, Viktor Tóth1e

1Technical University in Zvolen, T.G. Masaryka 24, Zvolen, SK 960 53, Slovakia.

aizdinsky@tuzvo.sk, bkudela@tuzvo.sk, czuzana.vidholdova@tuzvo.sk, dreinprecht@tuzvo.sk, eviktor.toth1989@gmail.com

KEYWORDSparticle boards, PET, properties, mould test

A very serious environmental issue at the present is waste disposal. The concern is about individual components of communal waste as well as about waste produced in various industrial branches. Primary important is the problem of waste from polyethylene terephthalate (PET) packing materials, especially PET bottles. Recycling methods for PET packing materials are sought to obtain raw materials with specific secondary use. One of such possibilities arises also in wood industry (Izdinsky et al. 2013).

In the recent years, the research has mainly been focused on supplementing ligno-cellulose plants and their lignified parts and also supplementing old, recycled wood in wooden materials manufacturing (Barbu et al. 2013).

Another approach is to combine wooden components with synthetic thermo-plastic materials (PP, PE, PVC, ...). In this way are obtained new materials recognised as wood-plastic composites.

Alternatively, production of new design products (Fig.1) utilizing PET waste (Tóth et al. 2012).

Figure 1: A seat with netting bonding from PET bottles

The aim of this work was to prepare a wood particle board supplemented with PET flakes and to study how the amount and allocation of PET component in wood particle boards affected selected physical and

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mechanical properties of such modified materials and also antimicrobial properties - resistance to microbial attack against moulds.

Moulds (mixture - Aspergillus niger Tiegh., Penicillium sp.,..) in the experiment were used from Collection of Wood-damaging Fungi in the Mycological Laboratory at the Faculty of Wood Science and Technology of the Technical University in Zvolen.

By microscopic analysis in the surface layers, under a temperature of near 200 °C, some PET flakes were melting; the core layers, the pressing temperature decreased to about half the value on the board surface. Under this temperature, the PET flakes maintained their original shape and did not link with the wood particles (Fig.2).

Figure 2: Middle layer of particle board with occurrence of melted and non-melted PET particles.

The PET admixture resulted in poorer mechanical properties; on the other hand, it improved the boards´ resistance against water (reduced thickness swelling and water absorption). These properties also depended on the amount of PET flakes added into the boards as well as the location of this flakes within the board. PET flakes added into the particle boards unincreased resistant against moulds.

REFERENCESBarbu M. C., Réh R., Çavdar A. D. 2013. Non-Wood Lignocellulosic Composites. In: Research Developments in Wood Engineering and Technology, edited by Alfredo Aguilera and J. Paulo Davim. Non-Wood Lignocellulosic Composites, Chapter 8. Hershey PA : IGI Global: 281-319.

Iždinský J., Tóth V., Kúdela J. 2013. Polyethylene terephthalate recycling in particle board production. In: Wood the best material for mankind, edited by Jozef Kúdela and Marián Babiak. Zvolen : Arbora Publishers: 93-97.

Tóth V., Pomikala R., Jerz J. 2012. Patent. Slovak Republic: 287936

ACKNOWLEDGMENTSThis work was supported by the Slovak Research and Development Agency under the contract No. APVV-0200-12. The authors would like to thank also to the COST FP1303.

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IMPACT OF WOOD PRESERVATIVE TREATMENTS ON MECHANICAL PROPERTIES OF E-GLASS/PHENOLIC COMPOSITE (FRP) REINFORCEMENT FOR LAMINATED WOOD BEAMSCihat Tascioglu1, Barry Goodell2, Roberto Lopez-Anido3

1Department of Forest Products Engineering, Faculty of Forestry, Duzce University, Duzce, 81620, Turkey.2Virginia Tech, Dept. of Sustainable Biomaterials, Virginia, USA.3University of Maine, AEWC, Maine, USA.

1cihattascioglu@duzce.edu.tr

KEYWORDSBridge structures, laminated beams, wood preservatives, glass fiber, pultrusion.

ABSTRACT

E-glass fiber/Phenolic matrix (FRP) material treated with common wood preservative chemicals including oilborne, acid and amine based waterborne treatments, and the effects on the mechanical properties of FRP material were investigated. The longitudinal, transverse tensile tests and short beam interlaminar shear tests were used for mechanical characterization of preservative-treated E-glass/phenolic pultruded composite. Although the longitudinal elastic modulus was unaffected, some longitudinal strength losses were recorded for waterborne preservative treated FRP coupons. The results were supported by scanning electron microscopy analyses of single glass fibers taken from failed FRP coupons.

BACKGROUND

Some examples of FRP-wood structural applications in civil infrastructure are FRP-glulam beams for bridge applications, FRP-gulam panels for bridge decks, FRP-glulam beams integral with a concrete slab and reinforced rail road ties. FRP reinforcements in the order of 1.1% in volume can increase the allowable bending strength of laminated beams by greater than 60% (Dagher et al 1998).These wood hybrids with proven mechanical properties, hold the promise of improving structures to support longer spans and heavier loads not previously possible with wood-only composites. However, to achieve long lasting service life structural timbers including laminated wood beams and wood/fiber reinforced polymer (FRP) hybrids must be protected by preservative systems when used in exposed outdoor environments against decay fungi, insect attack and, other environmental agents. When a post-treatment method (preservative application following composite fabrication) is used to produce reinforced wood composites, the composite is exposed to preservative chemicals as well as vacuum-pressure cycles, both of which creates stresses in the final product. The objective of this study is to characterize the effects of common wood preservative chemicals on the mechanical and design properties of E-glass fiber/phenolic matrix composites used in wood reinforcement.

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MATERIALS AND METHODS

Figure 1. Fiber architecture and composition of E-glass fiber/phenolic matrix composite fabricated for wood reinforcement.

RESULTS

Table 1. Selected property reduction values and statistical significance

Property Treatment Concentration (%) Reduction (%) p-value

Fxt

(Longitudinal tensile strength)

CCA1 0 25 0.0042.5 19 0.081

CDDC 5 28 0.0002.5 28 0.001

Fs

(Interlaminar shear strength)

Creosote 100 9 0.000

CDDC5 15 0.000

2.5 14 0.000

REFERENCEDagher et al. 1998, FRP reinforcement of Douglas Fir and Western Hemlock Glulam Beams, in International Composites Expo ’98, Nashville, TN.

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MECHANICAL PROPERTIES OF BIO-BASED FOAM IN ULTRALIGHT PARTICLEBOARDSMartin Rhême1, Ali Shalbafan2, Heiko Thoemen1

1 Institute for Materials and Wood Technology, Bern University of Applied Sciences, Solothurnstrasse 102, 2504 Biel-Bienne, Switzerland.

2 Department of Wood and Paper Science and Technology, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, Iran.

KEYWORDS Light-weight panels, Mechanical properties, Particleboard, Polylactides.

New uses trend and market demand for light-weight panels that can ensure a certain ease of transport and cost reduction. One of the strategies to reduce weight is the use of a sandwich structure with a low density core layer and particleboard as surface layers. Three layered sandwich panels can be produced by continuous process (Luedtke 2011, Shalbafan 2012a) without additional gluing between the face and core layers. The production process is schematized in Fig. 1 and the panel is referred as ultralight particleboard (ULPB).

Figure 1 Productio process of the ULPB consisting of 1) a consolidation phase of the surface layer, 2) an expansion phase and 3) a stabilization phase through active cooling.

Luedtke (2011) and Shalbafan (2012a and 2012b) used conventional non-bio based polymeric materials for in-situ foaming. Due to the increasing waste and environmental problems for traditional petroleum based foams, further development of the ULPB process towards a fully bio-based lightweight panel is in special focus. Thoemen (2012) and Yoon et al.  (2014) have developed a polylactic acid (PLA) based foam (PLA-PMMA 50-50wt%) using CO2 as blowing agent, fulfilling the requirements for the core layer materials of ULPB.

This paper presents the results of mechanical tests that were performed in order to investigate the elastic properties of the various possible core layers of the ULPB (see Fig. 2a). The elastic constants were determined during tensile, compression and shear tests with specimens that were machined out of ULPBs‘. A reference specimens of PLA-PMMA foam were also produced without the particleboard surface layer

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Figure 2 left: Cross section of the various panels. right: presentation of the correspond modulus of elasticity.

The results indicate that the nature of the polymer dominates the behavior for these three types of foam materials, followed by the foam cell sizes and foam precursor fusion. The foam cells size has significant effect on the values of young’s modulus. The cell wall thicknesses and the fusion between the foam precursors were the most predominant factor influencing the shear modulus. Young’s modulus are almost identical in tension and compression in case of homogeneous foam structures (EPS and RPLAPMMA foam), and seems slightly higher in compression for the heterogeneous foam structures (PLAPMMA and MS foams). Reference specimens of PLA-PMMA foam produced without the PB surface layer showed that the production process play a critical role on the microstructure of the foam and there is therefore the potential to increase the properties of the bio-base foam layer with further development of the production process.

REFERENCESLuedtke J. 2011. Entwicklung und Evaluierung eines Konzepts für die kontinuierliche Herstellung von Leichtbauplatten mit polymerbasiertem Kern und Holzwerkstoffdecklagen. Dissertation. Hamburg University, Germany.

Shalbafan A., Luedtke J., Welling J. and Thoemen H. 2012a. Comparison of foam core materials in lightweight wood-based panels made by continuous process, European Journal of Wood and Wood Products. 70(1): 287-292.

Shalbafan A., Welling J. and Luedtke J. (2012b). Effect of processing parameters on mechanical properties of lightweight foam core sandwich panels. Wood Material Science & Engineering. 7(2):69-75.

Thoemen, H. (2012). Ultra-light bio-based particleboard with a foam core. Swiss National Science Foundation, NRP 66, Resource Wood, http://www.nfp66.ch/E/projects/wood-material-for-components/ultra-light-bio-base

Yoon, Y., Plummer, C.J.G., Thoemen, H. and Manson, J.A.E. (2014). Liquid CO2 processing of solid polylactide foam precursors, Journal of Cellular Plastics, DOI: 10.1177/0021955X14537662.

ACKNOWLEDGMENTS

The authors greatly acknowledge the financial support of the Swiss National Science Foundation through the program NFP66 “Resource wood” and the grant IZK0Z2_162531.

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PURPOSE-DESIGNED BIO-COMPOSITE PLATES FOR THE BUILDING SECTORMichael Dorn1, Thomas Bader2

1Department of Building Technology, Linnaeus University, Sweden.2Vienna University of Technology, Austria.

1michael.dorn@lnu.se, 2thomas.bader@tuwien.ac.at

INTRODUCTION

DuraPulp is a wood-plastic-composite developed by Södra in Sweden. In its standard configuration, itconsists of soft wood pulp fibers and PLA with 70 and 30 % fraction, respectively. Un-activated DuraPulp comes in sheet-form or pressed in bales, already in the final mix-ratio of fibers and matrix material. By adding water, a watery pulp is formed which is then pressed under high temperatureinto the desired shape, hence becoming activated.

MECHANICAL PROPERTIES

The mechanical properties are so far only rudimentarily known; no wider study has been done so far.In preliminary tests, the expected stiffness and failure stress have been determined experimentally(see Figure 1). Stiffness was determined to be around 9000 MPa with a failure stress of 73 MPa. Clearly, non-linear behavior (plasticity) is observed.

Figure 1: Stress-strain curve of a tension test on activated DuraPulp with 30 % PLA content.

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MICRO-MECHANICAL MODELING

Experimental testing is a time-consuming process so that a micro-mechanical model for estimation of the elastic properties was set up, based on a Mori-Tanaka scheme with cylindrical inclusions in anisotropic matrix material. The input parameters are the elastic properties of the matrix and the fibers, respectively. Herein lays of course a major problem since the properties for the fibers are hardly available so that the values were (partially) estimated – within reasonable boundaries. The result is the full stiffness matrix of the composite (Figure 2). By performing a parametric study, it canalso be shown, which of parameters has significant influence or not. In the latter case, the actual properties do not be known precisely.

Figure 2: In-plane (E1 = E2) and out-of-plane (E2) stiffness of the composite in dependence of the E-modulus of the matrix (left) andthe volume fraction of the matrix (right).

COMMERCIAL USE

So far, a rather limited number of products have been produced such as a chair or lamp as well as first studies on plate-like material and for high-end packaging purposes. It is currently beingevaluated how to make use of the product in order to make it commercially available. A workpackage within the project Framtidens Biobaserade Byggande och Boende is dedicated to identify potential applications as well as to characterize DuraPulp (such as stiffness, strength, creep, wateruptake, bio-degradation etc.) with different compositions (such as thickness, material ratios). Potential fields of application are the use as sheeting material, the use of reinforcements inconnection details but potentially also for e.g. furniture.

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MORPHOLOGICAL CHANGES OF WOOD AFTER SHORT TERM NATURAL WEATHERING EVALUATED WITH SEMAnna Sandak 1, Jakub Sandak 1, Marion Noël 2, Solène Barbotin 2

1Trees and Timber Institute/National Research Council (IVALSA/CNR) Via Biasi 75, 38010 San Michele all’Adige, Italy.2 Bern University of Applied Sciences, Department Architecture, Wood and Civil Engineering Solothurnstrasse 102, Postfach 6096, CH-2500 Biel 6, Switzerland.

1anna.sandak@ivalsa.cnr.it, 1sandak@ivalsa.cnr.it, 2marion.noel@bfh.ch, 2solene.barbotin@bfh.ch

KEYWORDSSEM, wood weathering, wood morphology

Wood as a building material has been traditionally used for different types of load-bearing structures, decking, façades cladding, doors and windows. Recently the global trends of wood re-application as construction and façades materials are observed. It is due to nature-based inspiration, aesthetic, artistic and design requirements, as well as due to the trends of natural resources use in sustainable development. Wooden elements often suffer due to mechanical, environmental or biological alterations during their service life. The most susceptible parts are unprotected surfaces since they are mostly exposed to ageing, weathering or decay.

The goal of this work was to investigate the microstructure degradation of thin wooden samples exposed for short term weathering. Tests were performed in whole month of July, which according to previous research is considered as a most severe for weathering of wood micro-sections (Raczkowski, 1980).

Experimental samples were prepared from one piece of Norway spruce wood (Picea abies L. Karst.) on the slicing planner (Marunaka). The thickness of samples was ~100μm and the efficient surface exposed to weathering was 30 x 35mm (width x length respectively). Sets of samples were placed for natural exposure at 45º to the horizon, facing the four directions: North, West, East and South in San Michele, Italy. Samples were collected before exposition and after 1, 2, 4, 7, 9, 11, 14, 17, 21, 24 and 28 days of natural weathering. Scanning electron microscopy was used for evaluation of structural integrity of wood surface (Hitachi TM 3030 SEM).

Microscopic methods provided detailed information about surface morphology. The first sign of deterioration visible on the SEM images was the openings of bordered pits membranes in radial walls of early wood tracheids (Figure 1a). In the successive step the membrane covering the piths was broken, and presence of small diagonally oriented micro-checks was observed. With the progress of degradation enlargement of the pith crack was noticed being the result of the contraction of the cell wall caused by moisture variation. The advancement of weathering (UV degradation, leaching effect of water and mechanical damages caused by wind blow) leads to complete destruction of the pit membrane and crack propagation. The pit openings are then enlarged and in consequence the whole pit erodes away (Fig. 1b).

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a b

Figure 1: SEM images of early wood exposed to south for 2 days (a) and 21 days (b).

Scanning electron microscopy (SEM) was used here for examination of the morphological characteristics of naturally weathered thin wooden samples. It was confirmed that early wood was more susceptible to damage than late wood, which was explained by the fact that cells in early wood have thinner and weaker walls and in consequence has lower density. It was also observed that western and northern exposure sites are slightly less affected by weathering process. First signs of fungal infestation, not visible by naked eye were observed after 17 days of natural weathering.

REFERENCESRaczkowski J. 1980. Seasonal Effects on the Atmospheric Corrosion of Spruce Micro-Sections. Holz als Roh- und Werkstoff 38, 231-234.

ACKNOWLEDGMENTS

Presented work was conducted within The BIO4ever (RBSI14Y7Y4) project funded within a call SIR (Scientific Independence of young Researchers) by MIUR. The investigated samples were prepared under Round Robin Test within COST FP1006. The support of COST FP1303 for funding Short Term Scientific Mission of Dr. Anna Sandak is highly acknowledged. Authors would also like to thank Dr. Thomas Volkmer for inspiring discussion.

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NATURAL MATERIALS USED AS A REINFORCEMENT OF LUMBER Izabela Burawska1

1Warsaw University of Life Sciences, Faculty of Wood Technology, Nowoursynowska 166, 02-787 Warsaw, Poland.

1izabela_burawska@sggw.pl

KEYWORDSreinforcement, flax, hemp, bamboo

Any material can be used as a reinforcement, on condition it has higher strength or stiffness in  comparison to the initial, unreinforced material. Recently, new, eco-friendly materials of low production cost become the research objective. Table 1 presents the value of global production of  selected natural fibres. On the basis of its analysis it can be stated that it is possible to ensure the stability of fibres supply for reinforcement purposes.

Table 1. World production of fibres

The origin of the fibres Bamboo Jute Kenaf Flax Hemp Coconut Grass

World production [103 tons]

30 000 2 300 970 830 214 100 700

As a reinforcement layered laminate bamboo composite (LLBC) can be used. It is characterized by  high bending and tensile strength (table 3), resulting from specific structure of bamboo fibre. The fibre contains relatively high proportion of cellulose and lignin. Additionally the angle between microfibrils is relatively low. Other bamboo advantage is short renewability period.

Table 2. The chemical composition of selected natural fibres [2]

Specimen Density [kg/m3] Angle between the microfibrils [  ° ] Cellulose [%] Lignin [%]Coconut 1150 30 - 49 43 45Banana 1350 11 65 5

Sisal 1450 20 – 25 70 12Jute 1450 8.1 63 11.7

Bamboo 600 - 800 2 - 10 60.8 32.2

Recently flax and hemp fibres become more popular. This phenomenon can be explained by  the  increasing ecological awareness, manifested in the seeking of renewable, cheap in  production, biodegradable materials. Over the last three decades many research programs involved the search for a substitute for synthetic fibres. Widely used synthetic glass fibres can successfully be replaced by the flax fibres, because of its suitable mechanical properties (Tab. 3). The use of flax as a reinforcement of composite materials requires a careful

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selection of fibres. It  is common that some structural defects of fibres may occur. The most often defect of  fibres are  nodes, which initiate crack under loading.

Table 3. Mechanical parameters of selected natural materials [3]

Parameter LLBC Flax HempDensity [kg/m3] 900 1540 1590

Young’s modulus [GPa] 9.5 12 - 85 30 - 60Tensile strength [MPa] 110 600 - 2000 350 - 800

World production of hemp fibres is almost four times smaller in relation to the flax fibre production. However, it is predicted that in the future hemp fibres become the basis of European industrial crops. Hemp fibres can be a substitute for a synthetic glass fibres when light, rigid composite is needed (Fig. 1).

Figure 1. Mats used for timber reinforcement: flax (a), bamboo (b), basalt (c) hemp (d) [1]

The potential benefit of using natural composites instead of steel is increased resistance to fire as a result of lower conductivity (in case of reinforcement located inside the reinforced cross section. The research carried out under the supervision of Martin [4] shows that hiding the reinforcement material inside the reinforced cross section has a beneficial effect on the load-bearing capacity during a short-term fire. Additionally, when the bond between reinforcement and reinforced material is made of phenolic resin, very small amount of harmful substances is emitted in case of fire.

REFERENCES[1] Borri A., Corradi M., Speranzini E. 2013: Reinforcement of wood with natural fibers. Composites: Part 53: 1–8

[2] Jain S., Kumar R., Jindal U.C.: 1992: Mechanical behaviour of bamboo and bamboo composite. Journal of Materials Science 27: 4598-4604

[3] Lilholt H, Lawther J.M. 2000: Natural organic fibres. Comprehensive composite materials 1. Elsevier Science: 303–25

[4] Zeno M., Tingley D.A. 2000: Fire reistance of RFP reinforced glulam beams. World Conference on  Timber Engneering, Whistler Resort, British Columbia, Canada

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CHARACTERISTIC TIMBER DAMAGE IN CULTURAL MONUMENTS OF KOSOVO Agron Bajraktari1, Florit Hoxha2, Rrahim Sejdiu3

1University of Applied Sciences in Ferizaj, Kosovo; Prof. Asoc. Dr. / Rector.2University of Applied Sciences in Ferizaj, Kosovo; Assistant.3University of Applied Sciences in Ferizaj, Kosovo; Dean.

1agron.bajraktari@uni-pr.edu, 2florithoxha@gmail.com, 3rrahim.sejdiu@uni-pr.edu

KEYWORDSKosovo, moisture conditions, monuments, timber damage

The large number of cultural historic monuments made Kosovo an attractive place for foreign visitors. Religious and ethnic tolerance is a rule today and its citizens live together and appreciate their cultural monuments regardless of religion or ethnicity. This is also evidenced by the building and preservation of cultural facilities which were destroyed during the last war in the region.

Survey data shows that cultural monuments are quite vulnerable to damage with time, particularly the timber parts are the ones most subject to the risk of a biological degradation.

The main pests of wood parts are, as expected, insects and fungi. The insect species that damage mostly dry wooden parts of these cultural facilities are: old house borer (Hylotrupes bajulus) and common furniture beetle (Anobium punctatum de Geer). Fungi genera causing serious problems include Stereum and Donkioporia Expansa.

Kosovo climatic conditions with cold winters (up to -20oC.) and hot summers (up to + 35oC) are very convenient for the development of insects and fungi. April to June, appear to be most suitable months development of insect pests. This is because during these months, temperatures range between 12o and 35oC and the air humidity is high enough raising the moisture of the wood between the values 12 and 18% moisture, which is very suitable for development of insects. The biggest growth of fungi was observed in parts of basements where humidity is high and there is no light and good air circulation.

Figure 1: Tipical views of the exterior and interior timber uses in Kosovar cultural buildings

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Figure 1: Tipical views of the exterior and interior timber uses in Kosovar cultural buildings

REFERENCESMarku P, Bejtja. 2001. Imprenjimi i drurit, Tirana Albania.

Bajraktari A, Marku P. 2006. Përpunimi Sipërfaqësor i Drurit. Universiteti i Prishtinës, Fakulteti i Shkencave të Aplikuara, Ferizaj, Kosovo.

Sejdiu Rr, Bajraktari A, Bejtja A, Sejdiu M. Changes of Equilibrium Moisture during the Natyral Drying of Wood in the Territory of Kosova (for years 1960-2008). Report.

Barry A. Richardson. 1993. Wood Preservation, Second Edition, London · Glasgow New York Tokyo · Melbourne Madra.

Lato E, Quku D. 2008. Studim Druri, Struktura mikroskopike dhe vetitë e drurit,Tirana, Albania.

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LEACHING EFFECT OF RAIN IN OUTDOOR WOODEN APPLICATIONSLaszlo Tolvaj1, Robert Nemeth2, Denes Varga3

1,2,3Bajcsy u. 4., Sopron, Hungary, University of West Hungary.

1laszlo.tolvaj@skk.nyme.hu, 2robert.neme th@skk.nyme.hu, 3vargadenes@nyme.hu

KEYWORDSrain, leaching, UV radiation, IR spectroscopy

Beside sun radiation, the leaching effect of the rain is the second harmful factor effecting the degradation of outdoor wood. These effects were simulated by the following experiments. Beech (Fagus sylvatica L.) and spruce (Picea abies Karst.) samples were irradiated by mercury lamp for a day and then plunged into distilled water for one day. During the subsequent cycles the UV radiation was two days long but the water leaching remained one day.

Fig. 1A represents the effect of the 1-day UV treatment of spruce earlywood followed by 1-day of leaching in distilled water. The first difference spectrum presents the effect of UV treatment alone while the second one shows the effect of UV treatment and the subsequent water leaching together. The UV light induced lignin degradation represented by the absorption decrease at 1507 cm-1 is clearly visible. The water leaching did not affect this peak. The UV treatment produced great absorption increase in the unconjugated carbonyl region (1670-1820 cm-1). Two peaks arose close to each other during the one-day treatment. The intensity of this band was reduced considerably by leaching. The intensity of both peaks (1713, 1736 cm-1) decreased but to a different extent. The peak at 1713 cm-1 lost half of its intensity, while the other peak at 1736 cm-1 almost disappeared and remained only as a shoulder. The UV treatment generated absorption decrease and increase in the ether bond (1070-1200 cm-1) region (Fig. 1-2). The interpretation of these changes is difficult because of the roughness change (Tolvaj et al. 2011).

A B

Fig. 1 Absorption change of spruce earlywood (A) and beech (B) after 1 day UV treatment (UV) and 1 day UV treatment followed by 1 day water leaching (UV+w) (Csanády et al. 2015).

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Examining the absorption changes in beech (Fig. 1B), similar changes were found compared to spruce. The lignin content was not affected by the water leaching. Here the apparent difference is visible because of baseline shift. Two peaks were grown up in the non-conjugated carbonyl region (1670-1820 cm-1) as a result of the UV light induced lignin degradation. The stability of these two peaks is not equal. The peak at 1706 cm-1 was hardly affected by the water leaching while the other peak at 1767 cm-1 almost disappeared due to the water leaching.

To monitor the effect of periodic rainfall, samples were exposed to mercury lamp irradiation for one day followed by one-day water leaching. The repeated light irradiations were then 2 days followed by 1 day water leaching. For comparison, continuous light irradiation (without leaching) was also applied. Results of light irradiation are presented here up to the 7th day (4 cycles).

The lignin degradation was similar for both continuous UV treatment and UV treatment interrupted by water leaching in the case of all cycles. This experience confirms that the lignin degradation was not affected by water leaching. The results of the second series of treatment are presented in Fig. 2A. The 3-day continuous UV treatment created a little greater absorption increase at 1767 cm-1 than the treatment combined with leaching. The only important difference between Fig. 1B and Fig. 2A is that the K-M transformation lifts up the difference spectrum between 1070 and 1200 cm-1 because of the increasing surface roughness of the samples. The lignin degradation was continuous with increasing light irradiation time for both UV treatment types (with and without leaching). The absorption of carbonyl groups at 1767 and 1706 cm-1 increased continuously only in the case of continuous UV treatment.

A B

Fig. 2.79 Absorption change of beech after different treatments. Legend: UV irradiation in days + water leaching in days (Csanády et al. 2015).

The UV treatment combined with leaching resulted in a declining rate of carbonyl groups production. The intensity of the peak at 1706 cm-1 decreased slowly after the second cycle while the intensity of peak at 1767 cm-1 decreased rapidly. This phenomenon can be interpreted by the lack of the lignin molecules on the surface of the sample. The reduction of the absorption increase at 1767 cm-1 is clearly visible on Fig. 2B. This absorption increase was negligible even before the water leaching during the fourth cycles (7UV+3w). The next leaching (7UV+4w) reduced even this small positive peak. The fourth day of leaching created a negative peak at 1750 cm-1 (Csanády et al. 2015).

REFERENCESCsanády E., Magoss R., Tolvaj L. 2015. Quality of Machined Wood Surfaces. Springer: 67-91

Tolvaj L., Mitsui K., Varga D. 2011. Validity limits of Kubelka–Munk theory for DRIFT spectra of photodegraded solid wood. Wood Sci. Technol. 45. 1: 135-146

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DESIGN AND DURABILITY OF TRADITIONAL WOODEN HOUSES. A CASE STUDYMaria-Cristina Popescu1, Carmen-Mihaela Popescu2

1Petru Poni Institute of Macromolecular Chemistry, Iasi, Romania.

1cpopescu@icmpp.ro, 2mihapop@icmpp.ro

KEYWORDSdesign, durability, wood

Over the centuries, even from the beginning of civilization, wood played an important role in the human life; therefore, it has been used in many applications, from the domestic tools, furniture to different wooden structures – i.e. houses. Traditional houses from every country differ normally from one region to another, being influenced by different factors.

The wooden house in Bucovina developed over hundreds of years of permutations and assimilations, and in 19th century, became an original style which can be found in the entire region (Corduban and Polastri 2013). They are constructed entirely in wood, having as insulation for the walls a special recipe from soil with high clay and sand content, straw and horse manure, all mixed up with water. The finish layer was composed by soil with high clay and sand content and calcium hydroxide (Fig. 1).

Figure 1: Traditional wooden house in Bukovina region (left), insulation for the walls (right)

This study presents the style and structural characteristics of the house in Bucovina and will focus on the special features which ensured their durability and performances. This may be w applied when building new structures.

REFERENCES:Corduban C. G., Polastri, A. 2013. The Traditional Wooden House in Bucovina, a Model for Durability. Advanced Materials Research, 778:89-96

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COMPARISON OF A NEWAND A 40 YEARS OLD ROBINIA GLUED-LAMINATED LOAD BEARING ELEMENTJózsef Ábrahám1, Norbert Horváth2, Csilla Csiha3, Róbert Németh4, Miklós Bak5

University of West Hungary, Simonyi Karoly Faculty of Engineering, Wood Sciences and Applied Arts, 9400 Sopron, Bajcsy-Zs. u. 4.

1jozsef.abraham@skk.nyme.hu, 2norbert.horvath@skk.nyme.hu, 3csilla.csiha@skk.nyme.hu,4robert.nemeth@skk.nyme.hu, 5miklos.bak@skk.nyme.hu

KEYWORDSdelamination, glued-laminated element, robinia

The topic of this research was the comparison of the delamination and mechanical properties of a new and a 40 years old robinia glued-laminated load bearing element. The old element was manufactured in 1974 by the firma Agrokomplex and it was used in the spa in Harkány (Hungary) until 2014. The element was manufactured from 47 lamellae and its dimensions were 95×850×15000 mm (Figure 1). The glue used for the old element was a phenol-resorcinol glue with the name Aerodux 185 D from the company Dynea. This glue is a wide-range glue, as it is recommended for every wood species and for utilisation under both dry and wet circumstances or at even high temperature.

Figure 1: Cross section of the 40 years old glued-laminated robinia element

The glue used for the new element was a Jowapur 686.60 one-component fibre-reinforced PUR-glue. It is recommended for glued-laminated structures. The investigated properties were delamination (EN 391:2002), bending strength of the material (EN 310), moisture content, density, surface roughness, bonding quality (EN 314-1 and 2:2004).

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The results of the delamination test of the old element showed that some glue layers were delaminated exceeding the limit defined by the standard. The effect of that can be the loss of the load bearing capacity. Part of our investigation was to produce a new element by using modern materials and technologies and compare the properties with the old element. In case of the new element the delamination occurred even before the delamination test. The main question about this result is that is the used glue suitable for the gluing of robinia, however according the utilisation instruction of the manufacturer only mentions the larch from the wood species which the glue is not suitable for. This is because robinia contains a high amount of extractives which can inhibit the bonding between the glue and the wood material.

The exposure during the utilization of the old element was quite high, as it was working in a spa under highly moist conditions. It was exposed in this environment also to dissolved salts in the thermal water. The result of these circumstances is a high degradation of the wood material and the gluing quality as well. This was well explained by the low value and high variance of the bonding strength (shear strength).

However, the material of the old element would fit in the GL 24h bending strength category according to the standard EN 1194, but the bonding quality is below the regulations of the standard EN 314. This result confirms the replacement of the elements after the 40 years of usage.

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EFFECT OF SAWING PATTERN AND SPECIES ON THE PERMEABILITY TO WATER OF TWO CONIFERS: RADIATA AND SCOTS PINEFernández-Golfin, J.I.1; Galvan, J.2; Conde, M.3; Conde, M.4

1INIA-CIFOR, Spain, Ctra de la Coruna km 7.5, E28040 Madrid.2CSIC-IETcc, Spain, C/ Serrano Galvache 4, E28033 Madrid.3INIA-CIFOR, Spain, Ctra de la Coruna km 7.5, E28040 Madrid.4University of Cordoba, Spain, Campus Univ. de Rabanales, Ctra. Madrid-Cádiz km. 396, E14071-Córdoba.

1golfin@inia.es, 2j.galvan@csic.es, 3mariaconde@inia.es, 4ir1cogam@uco.es

KEYWORDS wood permeability, sawing pattern

In the context of the national project BIA-42434R on the Evaluation of functional behaviour of wood in outdoor above ground applications seven different field testing devices, all containing seven 750x100x20 mm3 specimens cut from Scots, radiata and laricio pines (sapwood) and also from sweet chestnut, eucalypt, thermotreated radiata pine and spruce; were exposed to weather in seven different Spanish locations. All the wood specimens were monitored (Scanntronik Thermofox+Gigamodule devices) in terms of moisture content and wood temperature up to a period of three years. The positioning of wood specimens and the MC/T measurement procedure were the same than the one proposed by COST Action FP 1303 (Figure 1). The sawing pattern of all the specimens was closed to a tangential (pith outwards)

Fig 1. Outdoor testing device

After a complete year, all the measures from the different species, devices and provenances were compared showing a clear different behaviour of radiata and Scots pines in two places. Analysing the differences we realized that even though our great efforts to homogenise the sawing patterns in all the wood specimens, the ones in those localities had annual rings at 45º.

To assess whether the sawing pattern could explain, or not, the clear difference observed in terms of reactivity to rain water (velocity of absorption), 100x100x20 mm3 quartersawn (contact angle closed to 90º) and

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riftsawn (contact angle closed to 45º) samples of radiata and Scots pine were introduced into a climatic chamber provided with a rain system (Fig 2). To avoid the effect of end grain all the edges were sealed. All the tests were carried out in a temperature of 25ºC and the MC of all the test samples was monitored by the Scanntronik devices.

The artificial rain system was only activated during three days per week 1 min every hour. The dry period was composed of four days at 25ºC/50%HR. We repeated the weekly cycle three times and the experiment was also repeated three times. In Figure 3 it can be seen the average results obtained for the first cycle from the three different experiments.

Figure 2. Test samples in chamber

Figure 3. Test results. MC evolution in the first cycle (week)

Surprisingly the sawing pattern showed a big effect on the reactivity to rain water, explaining the differences we had in two different places

REFERENCESBrischke, C., Humar, M, Meyer , L, Bardage, S, Bulcke, JV den (2014). Cost Action FP 1303. Cooperative Performance Test. Instructions for participants

ACKNOWLEDGMENTS

The present work was done within the scope of the project BIA-42434R on the Evaluation of functional behaviour of wood in outdoor above ground applications

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HYDRO-MECHANICAL BEHAVIOUR OF AUCOUMEA KLAINEANAUNDER DRYING PROCESSSamuel Ikogou1, Rostand Moutou Pitti2,3,4, Serge Ekomy Ango4

1Ecole Nationale des Eaux et Forêts (ENEF), Libreville, Gabon.2Université Clermont Auvergne, Université Blaise Pascal, Institut Pascal, BP 10448, 63000, Clermont-Ferrand, France.3CNRS, UMR 6602, Institut Pascal, 63171, Aubière, France.4CENAREST, IRT, Libreville, Gabon.

2,3,4rostand.moutou_pitti@univ-bpclermont.fr

KEYWORDSTropical environment impacts, Aucoumea Klaineana, fracture process, drying strains

Before the Cop21 forum, we know that environmental issues oblige wood and wood products to take an important place in our life due to their ecological impact in Europe and in equatorial regions such as Gabon, which concentrates various and unknown tropical species. Okoume (Aucoumea klaineana), one of the well know tropical specie, is used extensively in building, veneer, finished or semi-finished products and in the design of the paper. In timber structure, Okoume is often used after drying but also immediately after cutting. However, his mechanical behavior during drying plays a decisive role in the development of defects (Moutou Pitti et al 2013). This fact induces the necessity to study this important specie submitted to natural drying process.

MATERIAL METHODS AND RESULTS

The experimental device is composed of: a testing table, a scale, a thermo-hydrometer, a marker and a digital camera. A green wood slice (okoume) with a thickness and diameter is considered, Figure 1 (a). Before test, the slice is conditioned in water in order to guarantee its saturation. The marks are put on the slice to measure displacements during the drying process with a camera. In this case 6 radius and 4 Crowns around the center have been drawn, Figure 1 (b). The slice is finally positioned on the balance in order to measure the mass loss. Figure 1 (b) presents the cracked slice at the end of test after 7 days with final internal moisture content of 10%. The environment conditions of the experimental chamber are and . The mass loss, displacements and crack evolution are simultaneously recorded over time until the moisture content balance is achieved.

Fig. 1 (a): Experimental device. (b): Cracked slice with radius R and crowns C at the end of drying (10%)

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Two tests have been performed in order to compute the radial strain , tangential strain and shear strain according to the expression proposed by Guitard (1987) and Palka (1973)

EQUATION 1

is the volume mass. In this work, the obtained elastic moduli are compared with the values given by Guitard only for Test 2, Table 1. We observe important differences in the case of and

Tab. 1 : Comparis on of obtained elastic moduli with Guitard data

H(%) Mv (g/cm3) Er (MPa) Et (MPa) Grt (MPa)Test 2 12,04 0,42 1040 448 174

Guitard 14,30 0,42 1170 736 70

Figure 2 (a) shows the evolutions of radial strains versus internal moisture content. We can deduce that the point saturation fibre of Okoume is around 30%. Figure 2 (b) shows the evolution of tangential strains versus time after 250 h. We observe that strains in the heart of the slice are greater than the periphery; also, the influence of crack that occurs approximately 4

days after the start of the test, is observed. This defect is justified by a sudden decrease of tangential strains

Fig. 2 (a): Evolutions of Radial strains vs. moisture content. (b): Evolutions Tangential strains vs. time

This work is devoted to the knowledge of mechanical behaviour of tropical specie Aucoumea klaineana submitted to drying process. The PSF (30%) has been obtained by following the evolutions of radial strain versus internal moisture content. Also, the tangential strains have shown that the deformations are greater at the center than at the periphery and are perturbed by the apparition of crack 4 days after the beginning of test. In the coming works, a numerical finite element model will be developed in order to simulate the crack phenomenon in this tropical specie. The main goal is to know the real impact of environmental effects in timber structures under various loading conditions.

REFERENCESGuitard D. (1987) Mécanique du matériau bois et composites. Collection Nabla, Cepadues Edition, 238 p.

Palka L.C. (1973) Predicting the effect of specific gravity, moisture content, temperature and strain rate on the elastic properties of softwoods. Wood Science and Technology, 7:127-41.

Moutou Pitti R., Dubois F., Sauvat N., Fournely E. (2013) Strain analysis in dried green wood: Experimentation and modelling approaches. Engineering Fracture Mechanics, 105:182–199.

ACKNOWLEDGMENTS

The authors would like to acknowledge the National Agency of Research (ANR) for its financial support of this work through the project CLIMBOIS ANR-13-JS09-0003-01 as well as the labelling of the ViaMéca French cluster.

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THE IMPACTS OF THE CONSTRUCTION AND SURROUNDING CONDITIONS ON BIODETERIORATION OF WOODEN WINDOWS Zuzana Vidholdová1a, Ladislav Reinprecht1b, Stanislav Jochim1c, Ján Iždinský1d

1 Technical University in Zvolen, T.G. Masaryka 24, Zvolen, SK 960 53, Slovakia.

azuzana.vidholdova@tuzvo.sk, breinprecht@tuzvo.sk, cjochim@tuzvo.sk, dizdinsky@tuzvo.sk

KEYWORDSwooden window, design, microorganisms, decay

Service life of wooden windows in buildings is usually from 30 to 70 years (Brischke and Rapp 2010, Menzies 2013). It can be increased by: (1) a correct design, (2) using of more durable wood species, (3) a convenient surface treatment, and (4) a regular maintenance. However, the use of wooden windows in extreme climate conditions, e.g., a very high relative humidity of air in interior and water condensation, can create their damage with bacteria, moulds, staining fungi or even decaying fungi and boring-insects. The effects of exterior environmental impacts (rain, sun, etc.) and water condensation can be significantly enlarged with an inconvenient construction type of wooden frames. So, this combination results in a synergistic effect for biological damage not only of old windows but also of modern wooden windows, e.g., of euro-windows (Fig. 1)

Figure 1: The biodeterioration of wooden windows: a) Trametes versicolor, b) moulds, c) Gloeophyllum sp.

The basic design aspects for wooden windows to prevent their damage with wood damaging fungi are as follows:a quality of construction design for detail of the glazing in the window wooden frame,

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· a quality of insulating triple or double glazing,· a correct installation of a wooden frame with a bordering wall of the building,

To other important factors effecting the life time of wooden windows belong:

· a quality coating system, · a suitable maintenance.

The main objective of presented case study is to establish the effect of wood window’s design on their biological damage and analyses of poor design factors (Fig. 2).

Figure 2: Design aspects of wooden windows to prevent biological damage

A – incorrect → from the points No. 1, 2 and 3

1 = it prevents flow of a hot and wet air from interior to the detail of glazing; in this case it is without a leak, so then a higher risk of a water condensation on double-glass and an increase of moisture content of wood occur;

2 = triple-glazing is a better as double-glazing; in both cases, the space between glasses should be hermetically closed with an aluminium strip, with the aim that no oxygen and/or moisture needed for microorganisms will be transported here and to wood as well,

3 = ventilation groove under the glazing; if it is leaking then a cold air from exterior and a warm air from interior are here mixed with a following condensation of the cooled air from interior.

4 = surface coatings (other aspects, i.e., weather protection and regular maintenance).

B – correct

REFERENCESBrischke C., Rapp, A. O. 2010. Service life prediction of wooden components – Part 1: Determination of dose-response functions for above ground decay. IRG/WP 10-20439, 14 p

Menzies G. F. 2013. Whole life analysis of timber, modified timber and aluminium-clad timber windows: service life planning (SLP), whole life costing (WLC) and life cycle assessment (LCA). Report for the Wood Window Alliance, Institute for Building and Urban Design, Heriot Watt University, 39 p.

ACKNOWLEDGMENTS

This work was supported by Slovak Research and Development Agency - contract APVV-0200-12.

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WOODBUILD – KEY RESULTS AND THOUGHTS FOR FUTURE WORKJöran Jermer

SP Technical Research Institute of Sweden, Box 5609, SE-114 86 Stockholm, Sweden.

joran.jermer@sp.se

KEYWORDSWoodBuild, service life, decay, mould, exposure, resistance

The durability of building materials is a key issue of the European Construction Products Regulation (CPR), and the competitiveness of timber is highly dependent on its durability and how this is shown in a credible way. However, engineering methods in this area are rare or missing. The most important goal of the Swedish research programme WoodBuild, that was conducted between 2008 and 2013, was to provide practical, feasible engineering tools for architects and engineers to design for durability and estimation of service life of wood and wood based building components and structures, exposed in outdoor situations above ground (UC 3 according to EN 335-1) with respect to decay, and in the building envelope (UC 2) with respect to initiation of mould.

The methodology developed was based on an approach to try to use a similar procedure as for structural design, where the design condition is expressed as ”load effect” < “load-bearing capacity”, and a limit state associated with collapse or other forms of structural failure.

The performance of a wooden construction is affected by various factors with respect to:

a) The exposure (basically climatic conditions), and

b) The resistance to decay/mould (different materials have different resistance to decay and moulds)

Thus, a design condition for durability based on ”Exposure” and ”Resistance to decay/mould” was proposed accordingly: The exposure (”load effect”) < The resistance (“load-bearing capacity”) and a limit state expressed as onset of decay (rating 1 according to the stake test standard EN 252) and onset of mould (rating 2 according to Johansson (2012)).

Based on this new approach the work finally resulted in two guidelines, one for moisture safe design of the building envelope containing materials critical to moisture (Thelandersson et al), and one for guidance on design and selection of material for wooden constructions outdoors above ground (Isaksson et al).

Focussing on the guide for moisture safe design of the building envelope, the exposure in this case is relative humidity and temperature close to the material surface and depending on the inner and outer climate as well as the design of the construction. The relationship between a general time dependent exposure and material resistance is described with the so called MRD model (Mould Resistance Design), also developed within WoodBuild. For a given time variation of relative humidity and temperature and a specific material this model will give an MRD index that will help to evaluate the risk of onset of mould. The guide describes a methodology for evaluating constructions with respect to their design and climate on their geographical location. The methodology is particularly useful for comparing moisture safety of alternative design solutions.

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The work conducted within the WoodBuild programme has resulted in considerable progress with an engineering approach in designing the building envelope and wood constructions above ground with respect to service life issues. There is, however, a number of major challenges for further improvement, such as:

· The output from the design tools agrees reasonably well with experience from practice but more reality checks are needed. E.g. scientific evidence for identifying well-working solutions with respect to moisture safety of the building envelope is scarce.

· Quantification of exposure seems to give reasonable results but has to be further developed

· Quantification of resistance is still difficult for many materials/species. Further work needed. How to deal with resistance to insects, e.g. termites?

· To find the right balance of risk is a challenge due to large variability of material response as well as exposure

Last but not least, a major challenge is to encourage specifiers and architects to use the guides and give feedback from practice for improvements.

Figure 1: Comparison of planed spruce exposed at constant humidity vs cyclic humidity.

REFERENCES

Johansson P. 2012. Critical Moisture Conditions for Mould Growth on Builiding Materials. Licentiate thesis. Lund University, Report TVBH-3051.

Isaksson T., Thelandersson S., Jermer J., Brischke, C. 2015. Beständighet för utomhusträ ovan mark

Guide för utformning och materialval. Lund University, Report TVBK-3066.

Thelandersson S., Isaksson T., Niklewski, J. 2015. Fuktsäker utformning av klimatskiljande byggnadsdelar med fuktkänsliga material. Vägledning för projektering och riskvärdering. Lund University, Report TVBK-3066.

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THE CHALLENGE OF BUILDING WITH BIOBASED MATERIALS IN TERMITE AREASLina Nunes1,2, Sónia Duarte1,2

1LNEC, Av. do Brasil, 101, 1700-066 Lisboa, Portugal. Emails.2 cE3c, Centre for Ecology, Evolution and Environmental Changes/Azorean Biodiversity Group and Universidade dos Açores, Departamento de Ciências Agrárias, Açores, Portugal.

1linanunes@lnec.pt, 1sduarte@lnec.pt

KEYWORDSBio-based materials; Buildings; Challenges; Preventive control; Termites

Termite problems in Europe are increasing mainly due to the spread of the native subterranean termites belonging to the genus Reticulitermes, the main subterranean termite group present in the continent, and also to the invasive drywood termite Cryptotermes brevis (Nunes et al. 2010; Ferreira et al. 2013).

In particular, subterranean termites require soil and high moisture contact to survive. Typically, attacks on buildings are initiated from a nest in the ground from which termites build galleries over piers or walls to attack the structures from below. Subterranean termites in buildings remain in contact with the central nest and with the soil (for moisture). Any cellulose containing material can be used as food source and other types of materials present may also be degraded. Once an infestation has begun, the control of Reticulitermes sp. is extremely difficult due to their social living habits and cryptic behaviour. Therefore, in areas where subterranean termite attack is possible, preventive actions are a fundamental practice (Nobre and Nunes, 2006).

These preventive measures are essentially of two types (Cruz et al. 2015): (1) reduce or eliminate the probability of attack, by placing the bio-based materials under natural conditions that prevent the establishment and development of the termites, being the available moisture the primary factor; (2) prevent the termite infestation establishment by applying chemical treatments or material modification techniques (for example, thermal modification), by implementing physical barriers or by choosing a more specific technique like baits, which can be further optimized by adding a baiting substance either to kill or to repel the termites.

The adoption of certain design features and proper maintenance and monitoring of the construction can also have a decisive effect on the conservation of wood and other bio-based materials (Nobre and Nunes, 2006), at least in situations where they may be subject to humidification, especially on roofs, ground floors, near bathrooms and kitchens. Critical aspects include proper ventilation of sub-floor areas, prevention of leakages and mainly avoidance of direct contact to the soil (Fig. 1) or use of adequate barriers (Fig. 2). An integrated approach to termite management seems necessary for an effective control with long term protection. Accordingly, control systems involving more than one preventive and/or curative measure, including improved design, constitute a better option

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Figure 1: Rehabilitation of a timber structure after severe termite infestation.

Figure 2: Metal shields to avoid subterranean termites on new construction.

REFERENCESCruz, H.; Jones, D; Nunes, L. 2015. Wood. In Materials for Construction and Civil Engineering. MC Gonçalves, F Margarido (eds.), Springer International Publishing Switzerland. Pp 557-583.

Ferreira, MT; Borges, PAV; Nunes, L; Myles, TG; Guerreiro, O; Scheffrahn, RH. 2013. Termites (Isoptera) in the Azores: an overview of the four invasive species currently present in the archipelago. Arquipelago - Life and Marine Sciences 30: 39-55.

Nunes, L; Gaju, M; Krecek, J; Molero, R; Ferreira, MT; Bach de Roca, C. 2010. First records of urban invasive Cryptotermes brevis (Isoptera: Kalotermitidae) in continental Spain and Portugal. Journal of Applied Entomology 134 (8): 637-640.

Nobre, T; Nunes, L. 2007. Non-traditional approaches to subterranean termite control in buildings. Wood Material Science and Engineering 3-4: 147-156.

ACKNOWLEDGMENTS

To COST FP1303 for the chance to present this paper.

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FORMATION OF CRACKS IN WOODEN ELEMENTS – DESIGN, MOISTURE AND DURABILITY ASPECTS Linda Meyer-Veltrup1, Christian Brischke1, Christian Goritzka1, Ulrich Hundhausen2

1 Leibniz University Hannover, Faculty of Architecture and Landscape Sciences, Hannover, Germany. 2Norwegian Institute of Wood Technoloy (Treteknisk), Oslo, Norway.

1meyer@ibw.uni-hannover.de,1brischke@ibw.uni-hannover.de,2ulrich.hundhausen@treteknwisk.no

KEYWORDSCracking, Test design, Moisture content, Durability, Design details

The serviceability of wooden components exposed outdoors can be highly influenced by swelling and shrinking. For instance wooden windows or doors require high dimensional stability whereas fence posts are allowed to change in dimension without any loss of function. A second and even more crucial aspect when it comes to swelling and shrinking is the formation of cracks. Cracks are caused due to different tensions occurring between the wood surface and its interior parts (e.g. Sandberg 1999). Due to the anisotropy of wood the orientation of the annual rings in a wooden component influences swelling and shrinking processes. Hence the tangential surface is more susceptible to the formation of cracks than the radial surface, where latewood and earlywood are alternating and thus shrinkage movements and resulting stresses are buffered (Sandberg 1999; Sandberg et al. 2013).

In addition to anisotropy, crack formation is influenced by the dimension of the component. A study on differently sized test specimens made from Norway spruce and Scots pine sapwood has shown that the number and size of cracks increased with increasing specimen volume (Mehlich 2009). Besides optical appearance and mechanical characteristics it is assumed that the formation of cracks also influences durability (e.g De Groot and Highley 1995). However, studies performed by Brischke and Meyer-Veltrup (2015) who exposed differently sized test specimens over a period of five years have shown that there is no clear relationship between the specimen dimension and wood moisture content (MC) as well as resulting decay development. Although cracks lead to decay in many cases, interior rot can play a decisive role, too (Figure 1).

Fig. 1. Cross section scans of differently sized Norway spruce specimens after 5 years of exposure. Decay started from cracks in Q1 (100 x 100 mm²) and Q3 (50 x 50 mm²), from the bearing contact face in R1 (50 x 100 mm²), and from the interior of the specimens in Q5 (25 x 25 mm²)

(taken from: Brischke & Meyer-Veltrup 2015)

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To further investigate the influence of cracks on wood MC and the resulting decay risk, a test set up considering the effect of crack depth and width as well as number of cracks per surface area was developed. Therefore, spruce specimens (20/25 x 100 x 300 mm3) were prepared and provided with artificial cracks in form of differently sized notches. The different parameters varied as follows: 0 to 3  mm crack width, 5 to 15  mm crack depth, and 300  mm crack length. The number of cracks per surface area varied between 3 and 7 cracks per 100  mm specimen width. In addition, 45 different wood-based materials including preservative treated, chemically and thermally modified wood as well as wood polymer composites were exposed in the field to investigate their susceptibility to cracks and how the latter potentially affect wood MC.

The artificial cracks did not lead to significantly higher MC compared to controls without cracks. Only in few cases an increase in MC after rain events was faster in specimens with artificial cracks. The same was observed for the naturally developed cracks. When it comes to crack development the highest number of cracks per surface area after 11 weeks of exposure was found for Scots pine, Norway spruce and Siberian larch. Finally, it was found that the detection and documentation of crack development needs further investigation and development of suitable test and evaluation methods.

REFERENCESBrischke C, Meyer-Veltrup L (2015) Moisture content and decay of differently sized wooden components during 5 years of outdoor exposure. European Journal of Wood and Wood Products 73: 719-728

De Groot R C, Highley, T L (1995) Forest Products Laboratory Methodology for Monitoring Decay in Wood Exposed Above Ground. The International Research Group on Wood Protection, IRG/WP 95-20074

Mehlich R T (2009) Determination of moisture loads on differently sized wooden components exposed outdoors [in German]. Bachelor Thesis. Leibniz University Hannover.

Sandberg D (1999) Weathering of radial and tangential wood surfaces of pine and spruce. Holzforschung 53:355–364

Sandberg K, Mostolygin K, Hagman O (2013) Effect of lamellas annual-ring orientation on cracking of glulam beams investigated with computer tomography and image processing. Wood Material Science and Engineering 8:166–174

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THE PROBLEM OF EXTERIOR STRUCTURES BUILT IN NORTHERN SPAIN CLIMATES IN FIR AND SPRUCE DUE WOOD DESTROYING FUNGI ATTACKS. THE EXAMPLE OF A WOOD EXTERIOR STRUCTURE IN PONTEVEDRA, SPAIN AND THE IMPORTANCE OF DESIGN IN THE PERFORMANCEDavid Lorenzo1, Juan Fernández2, Manuel Touza3, Manuel Guaita1, Alfonso Lozano4, Josu Benito5,

Teresa de Troya2

1Engineering for Rural and Civil Development. Forestry School of Lugo, 27002 Campus s/n Lugo, Spain 2 Forest Research Centre (CIFOR) National Institute for agricultural and Food Research and Technology (INIA), 28080 Madrid Spain.

3 Galician Timber Technological Innovation and Services Centre. Galician Technological Park, 32901 San Cibrao das Viñas, Ourense, Spain.

4 Construction Engineering Area, EPS, Edificio Oeste nº 7, Campus de Gijón E-33203 Gijón, Spain5Tecnalia R& I, Área Anardi 5, 20730 Azpeitia, Guipuzcoa, Spain.

KEYWORDS Wood, use classes, exterior timber structures, weather conditions, design, performance, wood destroying fungi.

ABSTRACT

Use class concept is based on differences in environment exposures that can make the wood susceptible to biological deterioration. Exterior structures as: deckings, facades, bridges, etc., are examples of use class 3 situations, where the wood is above ground, exposed to the weather and wood destroying fungi and decays are possible depending on the climate (rain, temperature, etc.) and other conditions as: wood resistance, design and maintenance.

Designers working with wood in Spain don´t have reliable tools and methodologies which allow to properly assessing the functional performance and service life of wood in exterior constructions, depending on the local weather conditions and also on the adopted design and inherent wood material variables. The existence of Guidance documents developed in Northern Europe does not solve the problem in Spain, due the encountered very different climates, wood species and constructions system designs. There is a dose of degradation, performance and service life in exterior uses, inherent to each national geographical location (local climate) and depending on conditions of use of wood and details design as: sheltering, distance from ground, moisture traps, exposition to wind-driven rain, coatings, physical protection, ventilation, maintenance, etc. In short, all

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these factors generate finally irreversible changes to the wood material due to biological and abiotic agents, to the material itself, and also to climate and design details.

In the case of exterior structures built in sawn and glued laminated wood fir (Abies alba) and Spruce (Picea abies) in Northern Spain, present in many cases only after a few years after their installation several wood decay attacks and damages, that in some cases obligate to close them due several structural damages and to replace the wood structure by new one.

This exterior structure located in Pontevedra (Northern Spain), made in solid wood and glue-laminated wood Spruce, show degradations due wood decay in different parts depending on design details. In situ inspections considering the main factors, have been conducted to assess the real wood degradation status of this exterior structure, focusing on: wood species resistance, local climatic conditions and influence of design details in the kinetics of degradation in wood elements in this exterior structure. It is important to analyze their ability to withstand degradation over time in order to identify the parameters influencing performance and service life.

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INTERIOR DESIGNING WITH THE SURFACE DECORATIVE VENEERSMADE OF BLACK LOCUST (ROBINIA PSEUDOACCACIA L.)Roman Réh

Technical University in Zvolen, T. G. Masaryka 24, 960 53 Zvolen, Slovak Republic

reh@tuzvo.sk

KEYWORDSdecorative veneers, interior designing, veneer properties, black locust, veneering

This paper includes the recommendation to use the species black locust (Robinia pseudoaccacia L.) for the production of decorative veneers and interior designing. Black locust is an introduced species for Europe. This species grows under natural conditions from Pennsylvania along the Appalachian Mountains to northern Georgia and Alabama. It is also native to western Arkansas and southern Missouri. The greatest production of black locust timber is in Tennessee, Kentucky, West Virginia, and Virginia (Wiemann 2010). Black locust is a member of the family Leguminosae (Coombes 1992).

Black locust has narrow, creamy white sapwood. The heartwood, when freshly cut, varies from greenish yellow to dark brown. Black locust is very heavy, very hard, very resistant to shock, and very strong and stiff. It has moderately low shrinkage. The heartwood has high decay resistance. Besides of the decay resistance, the positive aspects of black locust is its dimensional stability. Black locust is used for round, hewn, or split mine timbers as well as fence posts, poles, railroad crossties, stakes, and fuel. Other uses are for rough construction and crating (Wiemann 2010, Cassens, 2007). Black locust is available as round or sawn timber, sometimes as veneers or as wood composites. Production of decorative veneers and interior designing are not reported extensively for the black locust (Lutz, 1971, Dianiskova et al. 2008, Barbu et al. 2014).

MATERIALS AND METHODS

Raw material for this research has Slovak origin and it was taken from Velke Zaluzie region. 6 veneer logs with a length of 138 -140 cm and with a diameter of 30.5 – 36.0 cm were not conditioned. Veneers were manufactured from fresh logs by off-center cutting in the Development workshops and laboratories of the Technical University in Zvolen. By means of interrupted off-center cutting new and interesting grains and textures of black locust were obtained. Veneers with the thicknesses of 0.5, 0.6, 0.7, 0.8, 0.9 and 1.0 mm were dried up to a moisture content of 7 ± 1 % by drying at a temperature 130 °C.

Black locust veneers were subjected to a number of technological test procedures:

Specific Glue Penetration to the Veneered Area Veneer Adhesion to the Particleboard Substrate Technological Properties of Veneers from the Aspect of Surface Finish

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The technological properties of veneers had been tested for surface finish by transparent paints and systems commonly used for interior designing. As a substrate, for all the tests three-layer particleboard reversibly veneered 300 x 600 mm; 150 x 300 mm and 100 x 100 mm in size was used.

Transparent coatings were used only. There exist two reasons for the use of final coating material; aesthetics and protection from the end use environment. The esthetics of the final product varies in many ways, depending upon the selection of the various topcoats available and upon how the final topcoat is handled. The ultimate protection for any wood product finish is dependent upon proper selection of the topcoat for a specific end use.

Three types of clean topcoats were used:

a) Polyurethane Lacquer LBA 26 + LGA 22 (Milesi) b) Nitrocellulose Lacquer C 1175 and C 1038 c) Water-dilutable Lacquer (Purlet)

RESULTS AND DISCUSSION

The test results on glue penetration to the veneered area revealed no substantial glue penetration within the spread range 140 – 150 g.m-2, inclusive of followed thicknesses.

Test of veneer adhesion to the particleboard substrate was influenced by the fact that the bottom part of particleboard of the most specimens was destroyed as a result of its imperfectness and not in the glue joint between the veneers and particleboard. Veneers in the majority of cases kept up with a higher intensity. The results suggest that adhesion of all six veneer thicknesses of black locust to particleboard substrate highly exceeds required value. Even in lower values of the glue spread, veneer adhesion to the substrate was gained with confidence.

Technological properties of black locust veneers from the aspect of surface finish were studied with a help of the veneer 0.7 mm thick which is a current thickness for decorative veneers and this thickness showed to be a convenient thickness according to the test of specific glue penetration to the veneered area.

Determination the Local Thickness of the Paint. The results of this test correspond to common values at the application of the paint types tested.

Determination of the Paint Adhesion by Means of the Screen Method (Cross Hatch). All finished types of paints provide acceptable adhesion degree independently of the type of paint used pointing to excellent or very good properties of black locust veneers with regard to the paint adhesion.

Determination of the Resistance to Hot Steam is purely the matter of coating compositions applied. Hot steam did not affect the quality of black locust veneers.

Determination of the Resistance to a Burning Cigarette (Burn Resistance). It follows from the test of paint resistance to a burning cigarette that all coating composition are less resistant to a burning cigarette.

Determination of the Resistance to Chemicals and Selected Consume Liquids (Spot Resistance) is in the system under examination a matter of the coating composition quality. All coating compositions used are suitable for surface finish of black locust veneers; no visible changes occurred at using any of the chemicals or consume liquids.

CONCLUSIONS

It can be said from the results of tests performed that black locust as an interesting species for interior designing is fully recommended. The quality of veneers made of black locust does not differ from the quality of commonly used veneers and thickness 0.6 – 0.7 mm can be recommended for interior designing. Glue spread 140 – 150 g.m-2 was proposed for particleboard.

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REFERENCESBarbu M.C., Irle M., Reh R. (2014): Wood Based Composites, Chapter 1 in Aguilera A., Davim P., Research Developments in Wood Engineering and Technology. IGI Global. Engineering Science Reference. Hershey, PA, USA, pp.1-45.

Wiemann M. C. (2010): Characteristics and Availability of Commercially Important Woods. Online at: http://www.fpl.fs.fed.us/documents/fplgtr190/chapter_02.pdf. January 8, 2016.

Coombes A.J. (1992): Trees. Dorling Kindersley Limited. London, p. 199.

Cassens D.L. (2007): Hardwood lumber and Veneer Series. Black Locust. Online at: https://www.extension.purdue.edu/extmedia/FNR/FNR-277-W.pdf. January 8, 2016.

Lutz J.F. (1971): Wood and Log Characteristics Affecting Veneer Production. Forest Service research paper, Forest Products Laboratory, Madison, WI, 1971, pp. 1-35. http://www.fpl.fs.fed.us/documnts /fplrp/fplrp150.pdf.

Dianiskova M., Babiak M., Tolvaj L. (2008): Color Homogenisation of Cherrywood (Cerasus avium L.) and Black Locust (Robinia Pseudoaccacia L.) During Steaming. Wood Research, 53 (4), pp. 45-58. ISSN 1336-4561.

ACKNOWLEDGEMENTS

The research described in the paper presented was supported by grant No. 1/0538/14 from the Slovak Grant Agency and by the Slovak Research and Development Agency under the contract No. APVV-0200-12. The author would like to thank the agencies for the support of this research.

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PERFORMANCE OF WINDOWS MADE OF THERMALLY AND NON-MODIFIED NORWAY SPRUCE (PICEA ABIES L.) IN DIFFERENT CLIMATIC CONDITIONS Aleš Ugovšek1, Barbara Šubic1, Gregor Rep2, Miha Humar3, Boštjan Lesar3, Nejc Thaler3, Christian Brischke4,

Dennis Jones5, José Ignacio Lozano6

1M SORA d.d.2Silvaprodukt d.o.o.3University of Ljubljana, Biotechnical faculty, Ljubljana, Slovenia. 4Gottfried Wilhelm Leibniz Universität Hannover, Institute of Vocational Sciences in the Building Trade.5SP, Technical Research Institute of Sweden, Department of Sustainable Built Environment.6Tecnologías Avanzadas Inspiralia S.L..

3bostjan.lesar@bf.uni-lj.si

Certified timber passive windows (M SORA Nature Optimo XLT) made half of NMS and half of Silvapro® TMS are exposed in different parts of Europe, including sites with extreme climatic conditions. The selected test sites are located in Slovenia (Žiri and Ljubljana), Germany (Hannover), Sweden (Skellefteå), and Spain (Madrid). Three windows are installed in test objects with regulated internal temperature of 25 °C which are constantly rotating with a frequency of one revolution per hour to diminish the effect of orientation of the test object.

Windows are surface treated with (I) naturally based Silvacera® wax (Silvaprodukt d.o.o.), which was developed within the WINTHERWAX project, (II) commercial synthetic coating and (III) commercial oil (both Remmers Baustofftechnik GmbH). Each window is equipped with sensors (Scanntronik) measuring surface temperatures (Thermofox) on inner and outer side of the window profiles, and sensors measuring wood moisture content

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(Gigamodule) in the core of the window profiles. Beside these measurements, colour changes of windows and façade elements are recorded after specific time periods with a transportable colorimeter (Erichsen).

First results show that the TMS parts of window have lower moisture content and that surface treatment has effect on it. Colour changes of windows are influenced by thermal treatment and surface coating.

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DURABILITY IS IN DETAILS - EXAMPLE OF A RECENTLY INSTALLED TIMBER CLADDING IN ZAGREB Vjekoslav Živković1, Hrvoje Turkulin2

1Faculty of Forestry, University of Zagreb, Svetošimunska 25, 10000 Zagreb, Croatia.2Faculty of Forestry, University of Zagreb, Svetošimunska 25, 10000 Zagreb, Croatia.

1zivkovic@sumfak.hr, 2hrvoje@sumfak.hr

KEYWORDStimber cladding, technical design, material

Durability of timber products outdoors, especially if used for cladding, can be achieved by proper material selection, technical design (physical protection, adequate detailing), surface protection and regular maintenance. In this work we analyse how these measures have been applied to a recently installed timber cladding in Zagreb.

Material used for this cladding is fir (Abies alba), without any surface treatment. This softwood species can be suitable for timber cladding from the aesthetical point of view, because any unprotected wood surface will become grey in continental Europe during the first year after installation. In terms of durability against decay, more durable species such as larch wood should have been preferred if the product is fully exposed to weathering. The simplest and the most effective way of extending the life of timber products outdoors is achieved by proper technical design. First of all, physical protection measures should be applied: timber products should be elevated from the ground (Fig. 1, Fig. 2) and protected by eaves and overhangs.

Figure 1: Timber cladding elements not sufficiently elevated from the ground

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Figure 2: Rain water can result with high moisture contents of wood not sufficiently elevated from the ground unless the grass is cut regularly

Other construction products like windows and doors should not be fully exposed, but withdrawn from the facade and shielded by cladding elements. Ends of cladding elements should be covered and sealed, especially if they are oriented horizontally (Fig. 3).

Figure 3: Fully unprotected ends of timber cladding elements

Secondly, vertically hung timber cladding elements fixed to horizontal battens from the rare side present a good example of adequate detailing. Cladding elements are neither chemically protected nor surface finished. Therefore, all timber parts should be regularly inspected for decay. Maintenance in this case can only consist of replacement of decayed parts.

The presentation brings also other important details whose aim is to ensure a long life of this and other claddings made of timber.

REFERENCESJirouš-Rajković V., Turkulin H., Sell J. 2002. Postojanost drva na pročeljima - 2. Dio: Površinska obrada drva na pročeljima (Durability of wooden facades - Part 1: Finishing of wooden facsdes). Drvna industrija, 53, 3:141-151

Turkulin H., Sell J. 2002. Postojanost drva na pročeljima - 1. Dio: Fizička i konstrukcijska zaštita (Durability of wooden facades - Part 1: Physical and structural protection). Drvna industrija, 53, 1:33-48

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PERFORMANCE OF A NEW BIO-BASED INSULATION BOARDPalumbo M1, Lacasta AM2

1,2Av. Dr. Marañón 44-50, 08028, Barcelona, Spain, EPSEB - UPC Barcelona Tech.

1mariana.palumbo@upc.edu, 2ana.maria.lacasta@upc.edu

KEYWORDSthermal insulation, corn pith, fire behaviour, mould growth

Intervention in the existing building stock is a key strategy for tackling the challenges posed by the European Commission urging member countries to reduce the internal GHG emissions by 20% in year 2020 and by 80% in year 2050, with respect to their 1990 emission levels. In Spain, it is estimated that, to meet these challenges, about 10 million dwellings should be insulated from now to the year 2050 (Cuchí and Sweatman, 2011). This fact, together with more restrictive regulations resulted in a significant increase on the use of thermal insulation materials in Europe. In consequence, the environmental impact embodied in these materials becomes a significant aspect to be taken into account. The development of bio-based thermal insulation materials can contribute to answer to both issues. Currently, there are several commercial examples of such materials, which are mostly based on industrial fibres (flax, hemp, kenaf, etc.), wood or sheep’s wool. The use of food-crop by-products is less common, but might be an interesting alternative for some countries such as Spain, where industrial fibre production is very marginal. In this work their use in building thermal insulation is proposed. In particular, a board made of corn pith bonded with sodium alginate is developed. The combination of rigidity with a low bulk density (about 55 kg/m3) is one of the advantages of this new material. Moreover, the amount of binder used is low (~5% in weigh) which limits the cost and the environmental impact of the material. The performance of the material is experimentally evaluated and compared to commercially available products.

The thermal conductivity of the material was found to be 0.038 W/mK. In order to evaluate the effect of RH on its hygrothermal performance, the material was exposed to cyclic changes in temperature and RH. Results showed that its hygrothermal performance was clearly affected by the moisture adsorption and desorption processes and that it was more favourable than that of polystyrene. Moreover, the fire reaction of the material was also investigated. Flaming combustion was analysed using a Pyrolysis Combustion Flow Calorimeter and a protocol to determine the ignition time and extinguishability. Results show that the fire behaviour of the material is better than that of polystyrene or polyurethane. It presents a fire load three times lower than polystyrene and a self-extinguishing behaviour. However, smouldering combustion was observed during the flaming tests (Palumbo et al. 2015). Thus, it was further investigated using an experimental set-up similar to the one described by (Hagen et al. 2011). Plain samples were compared to samples incorporating fire-retardants: ammonium polyphosphate (APP), boric acid (BAC) and hydroxide aluminium (HA). During the experiments, the evolution of the combustion was visualized with an infrared camera. Figure 1 shows an example of the resulting images. White colour represents the region where combustion is occurring. The best results were obtained for the APP and BAC samples.

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Figure 1: Infrared images of untreated (CA) and boric acid treated samples (BAC).

Finally, the mould growth resistance of the material was analysed too. Plain specimens were compared to treated specimens and to wood based materials. The samples were exposed to environments that are favourable to the development of naturally occurring spores. The treated samples showed an improved resistance to mould growth when exposed to 75% RH and 25ºC. However all the samples were highly affected when submitted to more severe conditions (95% RH, 25ºC), with the exception of those treated with boric acid, lime or stearates. The results show that bio-based materials present some advantages in terms of their fire behaviour and their hygrothermal performance when compared to conventional materials such as organic foams. However, their proper application is knowledge-intensive as these materials are more sensitive to moisture. Such sensitivity is behind its good performance but is also the reason preventing their widespread use in mainstream construction.

REFERENCESCuchí A., Sweatman, P. 2011. A National Perspective of Spain’s Buildings Sector: A Roadmap for a New Housing Sector. Working Group for Rehabilitation” GTR”.

Palumbo M.; Formosa J., Lacasta A.M. 2015. Thermal degradation and fire behaviour of thermal insulation materials based on food crop by-products. Construction & building materials 79: 34-39

Hagen B. C., Frette V, Kleppe G., et al. 2011. Onset of smoldering in cotton: Effects of density. Fire Safety Journal 46(3):73–80.

ACKNOWLEDGMENTS

The authors would like to thank Generalitat de Catalunya for the support provided under the project 2014LLAV00031 and under the PhD studentships FI-DGR. This work is also supported by MINECO (Spain) under the project BIA2014-52688-R.

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INFLUENCE OF THE RETENTION AND PENETRATION OF Cu BASED PRESERVATIVES ON THE PERFORMANCE OF SOFTWOODS IN GROUND Miha Humar1, Boštjan Lesar2, Nejc Thaler3, Davor Kržišnik4, Mojca Žlahtič5

1,2,3,4,5 University of Ljubljana, Biotechnical Faculty, Department of Wood Science and Technology. Jamnikarjeva 101, SI1000, Ljubljana, Slovenia.

1miha.humar@bf.uni-lj.si, 2bostjan.lesar@bf.uni-lj.si, 3nejc.thaler@bf.uni-lj.si, 4davor.krzisnik@bf.uni-lj.si,5mojca.zlahtic@bf.uni-lj.si

KEYWORDScopper based wood preservatives, retention, impregnation, performance, EN 252

Copper-based preservatives are one of the most important solutions for protection of wood in heavy-duty applications, as the majority of the alternatives were banned. After removal of copper-chromium based preservatives such as CCA and CCB from the market in 2006, copper-ethanolamine based preservatives became the most important group of copper-based wood preservatives in Europe. They will likely remain on the pedestal as long as micronized copper is not introduced in Europe as well. Copper-based preservatives are traditionally used for protection of softwoods in infrastructural applications like posts, bridges, vineyard poles, noise barriers, fences … In the Northern Europe, predominately Scots pine (Pinus sylvestris) was utilised for impregnation. Due to the lack of available Scots pine, Norway spruce (Picea abies) was used instead of pine in Central Europe as well (Humar et. al. 2006). One of the most important weakness of Norway spruce is insufficient permeability (EN 350, 2015). Therefore, some end users specifies different retention for Norway spruce and Scots pine (e.g. Willeitner, 2001). If wood preservatives are not applied correctly, premature failures will likely occur. Morell (2008) reported, that decay is the predominate reason for failure of utility poles in Pacific coast. More than 50% of failures are assigned to decay. Premature failures of wood could result in severe economic damage and influence negatively on public perception of wood. One of the reasons for premature failure is insufficient impregnation. In order to elucidate the importance of the proper impregnation procedure, sufficient retention and penetration present research was performed.

The research was performed on Spruce, Scots pine sapwood and European larch hartwood. Specimens of the EN 252 size (2.5 × 5.0 × 50 cm) were impregnated according to four various procedures as resolved from table 1. For impregnation, Silvanolin (Silvaprodukt, Slovenia) wood preservative solution was applied. Silvanolin consists of copper, ethanolamine, quaternary ammonium compound, boron and carboxylic acid. There were two concentrations of Silvanolin applied as resolved from table 1. Samples were exposed in the Field test site Ig, that is located approximately 15 km south from Ljubljana. Test was performed according to EN 252 procedure as can be seen in figure 1. Samples were exposed in 2009. First evaluation was performed in 2011, according to EN 252 rating scheme, where marks between 0 and 4 are applied (0 – no evidence of decay, 1 – slight attack, 2 – moderate attack, 3 – severe attack, 4 – failure).

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Figure 1: Exposure of the specimens according to EN 252 procedure

Due to the lack of space, only the data for Spruce wood are presented in respective abstract. First decay on control wood was evident after 2nd year (please note that there was no evaluation performed after the first year). The most prominent decay was determined on spruce wood, followed by Scots pine and the least prominent decay was determined at Larch wood. This field test site is rather wet, therefore the predominant type of decay was soft rot. Copper treatment, if applied correctly (with sufficient process) effectively protected wood against wood decay organisms. However, if wood is protected with shell treatment (treatment where only the outside layer is protected), decay is not prevented, but only slowed down. This can be seen from the specimens that were treated with dipping procedures, where copper penetrated up to 3 mm only. The decay rating of these specimens is very similar to control ones.

Table 1: Influence of the impregnation procedure and concentration of copper-ethanolamine preservative solution on performance of spruce wood in ground contact

Treatment procedure

Cu conc. (%)

Uptake of preservative solution (kg/m3)

EN 252 decay rating

2011 2012 2013 2014 2015

Dipping 8h0.25 46 0.3 1.0 2.4 2.6 3.00.5 46 0.9 1.3 1.7 2.6 2.9

Dipping 24h0.25 67 0.1 1.0 1.9 2.2 3.10.5 86 0.0 0.4 1.1 2.0 2.2

Vacuume0.25 195 0.2 0.3 1.6 2.0 2.80.5 258 0.0 0.0 0.1 0.4 0.8

Vacuume + pressure

0.25 560 0.0 0.0 0.0 0.4 0.60.5 425 0.0 0.0 0.0 0.0 0.2

Control / 1.8 2.5 3.2 3.3 3.5

REFERENCESHumar, M., Peek, R.D., Jermer, J. 2006. Regulations in the European Union with emphasis on Germany, Sweden and Slovenia. In: Townsend, T.G. (ed.), Solo-Gabriele, H.M. (ed.). Environmental impacts of treated wood. Boca Raton, FL: CRC/Taylor & Francis, 37-57.

Willeitner, H. 2001. Current national approaches to defining retentions in use. COST E22. 6.

ACKNOWLEDGMENT

The authors would like to acknowledge the support of the Slovenian research agency (ARRS) in the frame of the programme P4 0015 and project L4-5517.

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METHODOLOGICAL APPROACH TO THE EVALUATION OF THE CLT FOR USE IN SERVICE CLASS 3Galván, J.1, Troya, T.2, Oteiza, I.1, Martinez, E.3, Fernández-Golfin, J.I.2

1CSIC-IETcc, Spain, C/ Serrano Galvache 4, E28033 Madrid.2ETSA-UPM, Spain, Avda. Juan de Herrera, 4, E28040 Madrid.3INIA-CIFOR, Spain, Ctra de la Coruna km 7.5, E28040 Madrid.

1j.galvan@csic.es, 2enrique.martinez@upm.es, 3troya@inia.es

KEYWORDSclt, outdoor wood performance, wood construction, durability.

To perform a testing methodology for a material such as CLT, the handicap of the lack of regulations about it appears. This kind of products, called innovativing products (CPD), and in particular the CLT, which obtained the CE marked by CUAP procedure, has the problem of the lack of standardized tests specific for it.

The proposed methodology aims to advance knowledge of functional performance and durability of the CLT, under outdoor use (service class 3) with no ground contact (facades, bridges, etc.). Linking together the “material climate” (temperature and moisture content of wood), with inherent cumulative degradation of CLT in each weather or specific conditions of use.

Initially any kind of wood can be susceptible to becoming CLT. Due to the central European origin of the product, its workability and abundance in the environment, conifers are the first and main species that manufactured this product. It should be noted that in the mid-60s there were experiences in Spain with poplar CLT, not for construction applications. In this study, we selected spruce (Picea abies), suitable specie in the gluing processes, and Scots pine (Pinus sylvestris), one of the most common and commercial specie, and appropriate for outdoor conditions due to its easy acceptance of preventive treatment.

To study the structural durability of this material, in order to see its applicability in service class 3, different types of aging are proposed and further samples´ tests in order to make a comprehensive study to assess their suitability for use.

There are two types of aging process: natural aging of the material, in which it is directly exposed to the outside, allowing its degradation by the different meteorological agents, and artificial aging, produced in laboratory using different techniques.

Aging involves the introduction of a gradient in moisture content of wood to create internal stresses. This will result in tensile stresses perpendicular to the glue lines. Adequate adhesion of the layers and glue lines resistance to generated stress will be proved with that method. This moisture gradient is achieved by exposing the outside of the material or by providing laboratory water.

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Figure 1, 2 and 3: Images of CLT specimens of pine and spruce exposed to the outside conditions in Avila, Madrid and Seville respectively.

Laboratory tests shall be carried out by using climatic chamber and aging wheel.

Figures 4, 5, 6 and 7: Images of Ageing Wheel (FCBA) and the climate chamber (INIA) used for artificial aging of the specimens.

The outside test is performed exposing the material to climatic conditions of three representative Spanish climate types.

Samples obtained from outside conditions prototype, and laboratory samples will have the same size, in order to compare the results of artificial and natural aging.

After both aging processes, tensile test will be held for the purpose of analyzing how aging cycles affect the product, as well as the aging effect on the glue lines.

With this it can be checked if layers adhesion through the glue lines resists the generated tensions.

REFERENCESGalván J., Oteiza I., Fernández-Golfín J.I., Martínez E. 2014. Building with wood, evolution of sustainability in building materials. The case of the CLT. IETcc International Conferences. Madrid, Spain. Proceedings 114.

McClung R., Ge H., Straube J., Wang J. Hygrothermal performance of cross-laminated timber wall assemblies with built-in moisture: field measurements and simulations. Building and Environment, 71 (2014) 95-110.Xu W., Suchsland O. 1998. Variability of particleboard properties from single– and mixed–species processes. Forest Products Journal, 48, 9: 68–74

Regulation (EU) No 305/2011 of the European Parliament and of the Council of 9 March 2011 laying down harmonised conditions for the marketing of construction products and repealing Council Directive 89/106/EEC OJ L 88 of 4 April 2011

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HYGROTHERMAL PERFORMANCE OF CROSS LAMINATED TIMBER AS EXTERNAL WALL LAYER Villu Kukk1, Jaan Kers2

1 Chair of Woodworking, Department of polymer materials, Tallinn University of Technology, Ehitajate tee 5, 19086, Tallinn, Estonia, master student.

2 Chair of Woodworking, Department of polymer materials, Tallinn University of Technology, Ehitajate tee 5, 19086, Tallinn, Estonia, Professor,

1villu.kukk@gmail.com, 2jaan.kers@ttu.ee

KEYWORDScross laminated timber (CLT), hygrothermal test, indoor and outdoor climate

This paper describes the method for the hygrothermal test of CLT panels placed in one side open to indoor conditions (+26oC, RH25-30%) and other side into climate chamber in simulated external conditions (+6oC, RH80%). Test contained four CLT panel samples with length and width dimensions of 450x500mm. Two samples are with thickness of 100 mm where each layer is 20 mm thick. Other two samples are with lamella and panel thicknesses are 40mm and 200mm. Sample edges were covered with polyurethane acrylic paint in order to prevent the wetting of the sample sides.

Cracks are the main deformations that occur during the drying and by the wood shrinking. If the wood dries slowly and steadily, it is unlikely that the cracks occur. Fast drying causes major internal tensions in wood which, in turn, breaks wood structure and causes the formation of cracks. This project observed wood panels (CLT) behaviour in situation where material were drying in one side and absorbed moisture in other side. Before building up the test wall each sample were visible evaluated to determine existing cracks. The same procedure were repeated after the hygrothermal test to evaluate how much cracks came more and which size grew/shrank comparing initial evaluating.

Simulated external condition will be with temperature about 4-7°C with relative humidity about 80%. This kind of external condition is meant to represent Estonian weather in springs and autumns. Indoor climate temperatures were constantly +26oC with RH about 25-30. Therefore two main parameters are taken into account during this test: temperatures, both internal and external conditions, and moisture content.

As shown in Figure 1 four samples in test wall were separated and the spaces between them were compacted with thickening mineral wool and covered with vapour barrier tape (50 mm wide) to prevent air leaks.

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Figure 1: Scheme of test wall made from four CLT panel samples

Most important the external conditions were simulated by climate simulation chamber ILKA PTK-3018 and digital wood moisture content meter Testo 635. Temperature measurements were taken from each layer from each sample of CLT panel by loggers EasyLog GFX. During one month of testing the samples of CLT panels, temperature and MC of each panel layers were measured and checks appearance of each sample surfaces were observed.

Temperature growth rate of samples 1 and 2 (thicker panels) in first internal layers are low, near to 1%. In two middle layers the temperature growth rate in samples was in range 2-3% for thinner panels and 4-5% for thicker ones. External layers, L4 and L5, the temperature growth rate was highest, 7-8% in sample 1 and 8-10% in thicker sample 2.

From measured temperature and MC results it can be concluded that during one month of exposing panels to external condition with 80% of relative humidity only outer layers (L5) of CLT panels absorbed moisture. Moisture did not go through to the following layers. In internal layers the drying or moisture absorption was not significant.

From the results of checks initiation and propagation measurements it was clearly seen that checks widths in internal wide sides increased and in external wide sides decreased, but did not showed any spectacular differences in check appearing and growing between thick and thin panels. Thicker panels had much more checks than thin panel’s surfaces. Evaluating the visible checks in panels, it occurred that only sample no. 2 showed check growth extent in way that it can be considered as damage.

REFERENCESMcClung R., Ge H Straube J., Wang J. 2013. Hygrothermal performance of cross-laminated timber wall assemblieswith built-in moisture: field measurements and simulations. Building and Environment. Elsevier. pp 95-110

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A WIRELESS SYSTEM FOR MONITORING THE INTERNAL TEMPERATURE AND HUMIDITY VALUES OF DIFFERENT TYPES OF WOOD S. Aparicio1, J. Galván2, M.G. Hernández1, J.I. Fernandez-Golfin3, J.J. Anaya1

1CSIC-ITEFI, Spain, C/ Serrano 144, E28006 Madrid.2CSIC-IETcc, Spain, C/ Serrano Galvache 4, E28033 Madrid.3INIA-CIFOR, Spain, Ctra de la Coruna km 7.5, E28040 Madrid.

1sofia.aparicio@csic.es , 1m.g.hernandez@csic.es , 1jj.anaya@csic.es , 2j.galvan@csic.es , 3golfin@inia.es

KEYWORDSMonitoring, wireless sensor networks, wood, temperature and humidity.

Sensor technology plays an important and growing role in today’s industry and life. Many production processes rely on sensors for coordination and control. Sensors are crucial as part of security systems and also for monitoring environmental conditions or the structural integrity of buildings. Traditionally those sensors were connected by wires to some central computing device which processes and interprets the sensor signals. This wiring is expensive and severely limits the flexibility and reusability of the sensors. Therefore the use of wireless technologies is gained importance.

The aim of this work is to study how the environmental conditions affect the wood quality. For that purpose, a monitoring system provided with temperature and humidity sensors and developed by the authors, was deployed during 6 months in 3 different places with diverse environmental conditions: Madrid, Seville and Avila (Galván, 2016). This system is based on WSNs using Iris motes developed by MEMSIC Company (Aparicio et al. 2014). This platform was selected mainly because it is an open source wireless sensor platform with open access hardware and software designs.

On each city, a wireless system composes of 2 motes is being used. One mote is configured as a base station connected to a laptop for receiving the data, and the other one is sensorized to monitor every 5 minutes with 8 SHT75 sensors. The internal temperature and humidity values in two different basins made of wood, pine and fir, were obtained for six months. The system is controlled remotely using the teamviewer desktop and saving the data in the dropbox file backup. The problems identified in the monitoring and the solutions performed are the following:

1. Power outage of the computers receiving the data. This problem is usually solved in a few hours. Conventional computers are not restarted when the power supply returns, so the solution is to use low-power computers with independent power to keep operating during power outage.

2. Problems in the communication between the base and the sensorized mote. The solution is based on installing repeaters between the base and the sensorized mote to increase the power of the transmitted signal.

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3. Sensor faults due to water ingress. The solution has been to tilt the sensor cavity to avoid the accumulation of water. In later versions, Goretex filter will be used to allow entry of moisture but not water.

4. Condensation. It has occasionally occurred, mainly in the system of Seville where the highest relative humidity has been measured. When the sensors dried they start to work normally. The new generation of humidity sensors have a drying mode to remove condensation if it is occurred.

5. Dependence of the relative humidity with temperature. The relationship between the humidity and temperature of the cavity, and the moisture of the wood will be established by the Dyken procedure (Dyken et al. 2010).

CONCLUSION

The installed monitoring systems have proven that they are useful in the proposed application. A number of problems have been identified with an easy solution that will be implemented in subsequent applications. None of the identified problems compromise the results of the study that is being addressed in this work, since only a very limited amount of data has been affected and they almost no influence on the general behavior.

REFERENCESAparicio S., et al. Performance of a tree routing topology for wireless sensor networks using different platforms. Chapter 4 in Horizons in Computer Science Research, Vol 9. Nova Science Publishers, 2014.

Dyken T., Kepp H. Monitoring the Moisture Content of Timber Bridges. International Conference on Timber Bridges (ITCB 2010).

Galván J., eta al. Methodological approach to the evaluation of the CLT for use in service class 3. Technical Workshop: Designing with bio-based building materials - Challenges and opportunities. Madrid, 2016.

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SUSTAINABILITY INDICATORS SET FOR AGRICULTURAL RESIDUES BASED PANELS IN DEVELOPING COUNTRIESChristelle Ganne-Chédeville1, Raphael Maineiro2, Jan Grenz2, Ueli Jezler3

1 Institute for Materials and Wood Technology, Bern University of Applied Sciences, Solothurnstrasse 102, 2504 Biel-Bienne, Switzerland.

2 School of Agricultural, Forest and Food Sciences HAFL, Bern University of Applied Sciences, Länggasse 85, 3052 Zollikofen 102, Switzerland.

3 Center for Development and Cooperation CDC, Bern University of Applied Sciences, Solothurnstrasse 102, 2504 Biel-Bienne, Switzerland.

1gnc1@bfh.ch

KEYWORDSSustainability assessment, developing countries, particleboards, agricultural residues

Affordable building materials are commonly produced from wood. New techniques, however, enable the alternative production of panels out of agricultural residues (corn stover, rice husk, coconut fibers, groundnut shells, etc.) thus offering new economic opportunities for developing countries. While alternative panels reach the required technical standards, different practices and techniques result in very different sustainability performance. A tool for combining the evaluation of all life stages and the three sustainability dimensions (ecological, economical and societal capability) thus is needed to assess potentials and risks of these new products prior to their market introduction (Mgbemene et al. 2014).

The goal of the project was to develop an evaluation tool assessing the most relevant sustainability indicators for raw material extraction, manufacturing, use and end of life of panels (indoor application) made out of corn stover with its production being located in developing countries. The tool allows the comparison of different silvicultural and agricultural practices and technologies thus supporting decision-makers and stakeholders. Sustainability indicators and background data were largely adapted for comparison of a newly developed corn stover based panel bonded with tannin glue manufactured in Nigeria and traditional particleboards and plywood panels as manufactured in Switzerland.

Structurally, the tool is based on an Excel-based questionnaire being split into sections for raw material and production. Users are asked for selecting default answers and giving quantitative specifications. For raw material processes generic algorithms and valuation schemes were developed according to peer reviewed studies and published expert reports. 37 parameters being merged into 21 indicators were considered for silvicultural and agricultural practices. For the production section (from production to end of life stage) life cycle analysis and life costing analysis were used to assess 15 parameters being merged into 5 indicators. Table 1 shows a selection of parameters and indicators with their respective life stage, system and sustainability dimension.

Sustainability performance is assessed in four categories: best, good, moderate and insufficient sustainability practice in accordance to the first draft of SAFA guidelines (FAO 2013). Results are presented in tables and graphically in a spider web diagram (Figure 1).

Help function specify the required information and make the tool being applicable by non-experts. While the

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tool is already applicable, an expert review process and test of field applicability is planned for the future.

Figure 1: example of a comparative sustainability assessment of two systems based on silvicultural and agricultural residues raw materials.

REFERENCESFAO, 2013 SAFA Indicators. Sustainability assessment of food and agriculture systems. Food and agriculture organization of the United Nations (FAO).

Mgbemene C, Rosenkranz A, Pichelin F, et al (2014) Feasibility study on the production of particleboard from maize cobs, rice husks, and groundnut shells using Acacia mimosa tannin extract as the bonding adhesive. J Archit Eng 20:04013006. doi: 10.1061/(ASCE)AE.1943-5568.0000135

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BIO4EVER PROJECT CONCEPT TO PROMOTE THE BIO-BASED MATERIALS IN MODERN CONSTRUCTION SECTORAnna Sandak1, Jakub Sandak1, Bruno Simões2, Federico Prandi2, Raffaele Dei Amicis2

1Trees and Timber Institute/National Research Council (IVALSA/CNR) Via Biasi 75, 38010 San Michele all’Adige, Italy.2 Fondazione GraphiTech, Via alla Cascata 56/C, 38123 Trento, Italy.

1anna.sandak@ivalsa.cnr.it , 1sandak@ivalsa.cnr.it , 2bruno.simoes@graphitech.it , 2federico.prandi@graphitech.it 2raffaele.de.amicis@graphitech.it

KEYWORDSbio-materials, sustainable design, building envelope, service life performance

The trend for increase use of novel material solutions at reduced-costs through predictive design of materials and innovative production technologies is observed currently. As a consequence, higher numbers of well performing (also in severe environments) construction materials are available on the market. The expansion of bio-based products availability and its wide utilization in modern buildings is a derivative of the Europe 2020 strategies. As a result it is estimated that bio-materials will play progressively more significant role in the future, in order to assure the full sustainability of the construction sector.

The goal of BIO4ever project is to take an advantage of the exchange between different scientific disciplines, such as material sciences, wood technology, biology, building physics, engineering, architecture and information technology (IT), in order to demonstrate advantages of emerging bio-based building materials.

Today’s bio-based building materials, even if well characterized from the technical point of view, are often lacking of reliable models describing their performance during service life. The challenge is therefore to co-involve physics, chemistry and mathematics, as well as psychology and customer preference research in order to extend the length and time scales to which available models can be usable.

The project embraces a number of aspects such as:

· design and management of buildings and constructed assets

· proper choice of materials

· efficient energy use

· the physical, functional and aesthetical performances of building materials

· interaction with the urban and economic development and management.

The intention is to promote use of bio-materials in modern construction by understanding and modelling its performance as function of time and weathering conditions and to identify most sustainable treatments of bio-material residues at the end of life, improving even more their environmental impact.

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Three different approaches are used for samples degradation:

· natural weathering of bio-materials on the living laboratory - structure designed by Renzo Piano and installed at CNR-IVALSA (San Michele All’Adige, ITALY); samples will be exposed for different weathering doses/periods and characterized in the laboratory (2 replicates/biomaterial/cycle)

· natural weathering of bio-materials on the robotized stand, (South exposure, 45° inclination); samples will be automatically characterized daily with a multi sensor scanner installed on the stand (3 replicates/bio-material)

· artificial weathering tests: SUN-test, QUV and custom weathering machine (3 replicates/bio-material/test)

The output of the research will be tested with new generation of low-cost reconstruction and interaction tools developed within c-Space project. The digital models will be used for scientific visualization, controlling and monitoring of material deterioration on the building facades and for simulation and validation of the system. The tool developed within both projects will be dedicated for investors, architects, construction engineers, professional builders, suppliers and other relevant parties, including also final customers.

ACKNOWLEDGMENTS

The BIO4ever (RBSI14Y7Y4) project is funded within a call SIR (Scientific Independence of young Researchers) by MIUR. The c-Space received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 611040.

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USE OF BIO-BASED BUILDING MATERIALS IN TURKEY-PRESENT SITUATION AND FUTURE CHALLENGESNurgul Tankut1, Eser Sozen1

1Bartin University, Faculty of Forestry, Department of Forest Industry Engineering, Bartin, Turkey.

1ntankut@bartin.edu.tr

KEYWORDSTurkey, bio-based materials, building construction

Turkey is a major producer of basic building materials, especially competitive in producing steel, cement, ceramic, glass, natural stones, wood products and occupies a very important position in Europe (Republic of Turkey 2014). The use of bio-based materials has a long tradition in Turkey. These materials have been used as structural members, insulation or roofing in the construction sector for centuries but were widely replaced by industrial produced, mineral based materials in the last decades.

The traditional Turkish houses in Anatolia date back to in the 15th century and spread to Rumelia and to the other regions within the boundaries of the Ottoman Empire. Remaining examples which are still in good condition have been taken under conservation by Ministry of Culture and Tourism, UNESCO and the Council of Europe. Different architectural construction systems emerged in various parts of Anatolia based on environmental and climatic factors, convenient materials, easily obtainable, distinctive cultures, which are all infact interrelated and integrating regional features as different elements of the whole Turkish building concept.

Figure 1: Çanti (a), Hatıl (b), Hımış (c), Dizeme (d), Bağdati (e) and stone (f), applications in traditional Turkish construction (Doğangül et al. 2006).

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The historical method of construction is called as “çanti” (log house) in which logs slightly processed are overlapped and anchored at the ends. In the Hatıl construction, horizontal timbers embedded into bearing wall masonry. The hatıls when tied around the facade-side wall junctions did aid in reducing the significance of corner wedge failures. Hımış construction is described as a timber frame with masonry infill such as bricks, adobes or stones. Dizeme construction, wood were used as infill materials instead of masonry in forested regions. Short rough timbers elements called as “dizeme” were used as infill and they were nailed studs or horizontal framing elements. The purpose of wood infill usage to avoid their common early shear failure and falling out of the frame occurred for masonry infill. Numerous load paths are considered structurally redundant and provide an extra level of safety in earthquakes. Bağdadi construction where the voids between timber framing members is filled lighter materials or with trunk shells are transformed into a filling material by sand and lime mortar. The interior surfaces of walls are covered by lath and plaster work or wood, whereas the outer surfaces are either plastered or non-plastered or wooden plastered (Doğangün et al. 2006). Since located in a volcanic area, the basic input used in local architecture is easily workable calcareous stone in Mardin houses. From the point of view of the structural property, it is the weakest wall type. The peripheral ties used between the walls increase the strength of the stone walls.

Materials include straw bale and earthen construction including cob, adobe, wood, brick, rammed earth and compressed earth block that have been forgotten in the last 50 years due to lack of available information on material properties and seismic behavior combined with the challenges of durability perception. Building codes and engineering guidelines play an important role in supporting this shift to alternate construction materials. Compared to other European countries, the use of bio based building products in Turkey is quite low nowadays. Reinforced concrete and steel are used in the vast majority of existing and new buildings.

The observed thought after the destructive 1999 earthquakes are that the houses having been built with traditional construction techniques had little damage and did not cause too much life loss. An integrated and comprehensive approach will aid in understanding these materials, developing appropriate engineering design standards, implementation of technologies and educating building officials, builders and potential owners.

REFERENCESRepublic of Turkey. 2014. Ministry of Economy, General Directorate of Exports. Building Materials.

Doğangün A., Tuluk Ö. İ., Livaoğlu, R., Acar R. 2006. Traditional wooden buildings and their damages during earthquakes in Turkey. Engineering Failure Analysis, 13(6), 981-996.

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AUSTRIAN WOOD DESIGNER BUILDINGSMartin Weigl1, Michael Truskaller2, Martin Teibinger3, Franz Dolezal4

1,2,3,4 Franz Grill Str. 7, 1030 Vienna, Austria, Holzforschung Austria.

1m.weigl@holzforschung.at, 2m.truskaller@holzforschung.at, 3m.teibinger@holzforschung.at,4f.dolezal@holzforschung.at

KEYWORDSfire safety, acoustics, indoor air quality, haptics, surface sensation

Austria has a variety of national and federal building regulations and standards. Furthermore, voluntary regulations and singular building site related tenders are often applied. Such framework conditions directly influence application of wood for the built environment. By solving technical challenges as well as adaptation of regulations, application of wood and wooden products in this sector will be increased in future. If this is not possible, wooden products will be substituted.

Holzforschung Austria is constantly acting in this field, supporting the wooden industry in terms of research and development, external quality control, inspection and certification, as well as revision of regulations. With respect to building design, several topics are currently under investigation. Some important spotlights will be given from a technical point of view with an Austrian perspective.

The Austrian Institute of Construction Engineering (OIB) created a directive regarding building regulations for fire safety which is the basis for the harmonisation of the nine Austrian building codes. Later are actually enacted in eight regions. Essential changes for timber constructions concern the building class 5 (≤ 6 stories), wooden facades, and size of fire compartments for residential buildings. Recently and current research with respect to fire safety of wooden buildings is focused on improved wood/non-wood-composites, wood protection, timber construction, timber connection, service shaft and fire stops, planning guidelines, and applications in energy efficient buildings.

While wooden constructions show a good performance with respect to acoustic properties in the higher frequency range, performance at low frequencies is worse. Especially in the frequency range below 100 Hz, wooden constructions perform worse compared to other building products due to their relative light structure leading to low absorption. However, standardized testing devices don´t cover this frequency range due to reduced size of the test facilities. Hence, a novel testing device (Fig. 1) was designed based on simulations and recently erected within the “Acoustic Center Austria”, operated by Holzforschung Austria, TGM and Vienna University of Technology.

Indoor air quality often used to be focused on the reduction of formaldehyde emissions from products in the past. While formaldehyde is nowadays still in focus, especially due to the new classification as carcinogenic category 1B, also emissions of volatile organic compounds (VOC) are constantly of increasing interest. Besides product engineering towards reduced emissions, especially long term simulations and demonstrations are of high interest for wooden buildings. Model room experiments as well as real indoor environment measurements show significant reductions of organic emissions. Such emission developments can even be calculated based on adequate models.

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Haptic sensation of wooden surfaces is dependent on a variety of product properties. Especially material selection, material temperature, and surface roughness are the main factors influencing surface sensation in situations of physical contact. Furthermore, test persons usually can differentiate between natural and synthetic materials just by touching. Especially wooden products with natural surfaces feel more comfortable compared to other materials, both at low and increased room temperatures. Hence, such material properties are crucial for human comfort and should be considered more in building design.

Such technical aspects as well as human comfort are crucial for future applications of wood and wooden products within the built environment. Especially wood has a high potential to combine both functionality of a building and comfort in application.

Figure 1: The XL-acoustic testing device in process of integration of a specimen

ACKNOWLEDGMENTS

We like to thank all our co-workers doing excellent work within a variety of projects, most commonly funded by the Austrian Research Promotion Agency (FFG). Furthermore we kindly acknowledge any support from our business partners.

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CHALLENGES AND OPPORTUNITIES OF THE WOOD CONSTRUCTION SECTOR – INSIGHTS FROM THE INNORENEW COE MARKET ANALYSISMatthew Schwarzkopf1, Michael Burnard2, Amy Simmons3, Črtomir Tavzes4, Andreja Kutnar5

1,2,3,4,5University of Primorska, Andrej Marušič Institute, Muzejski trg 2, SI-6000 Koper.

1matthew.schwarzkopf@iam.upr.si,2michael.burnard@upr.si,3amy.simmons@iam.upr.si ,4crtomir.tavzes@famnit.upr.si,5andreja.kutnar@upr.si

KEYWORDSSlovenia, southern Europe, building certification, sustainability, renewable materials

In Slovenia, the wood construction sector has experienced less dramatic changes compared to the construction sector in general, especially during the economic crisis. Policy actions and people’s perceptions of timber architecture have influenced the sector, in recent years. This presentation will deliver key challenges and opportunities that were identified by market analysis performed in for the InnoRenew CoE project (2016).

Challenges:

· The majority of funds in the European construction sector will be spent on renovation. The Slovenian wooden construction industry is woefully underprepared to perform (large scale) renovations, as they still focus on new (prefabricated) construction.

· The are just a handful of manufacturers of cellulose insulation present on the Slovenian market. Other forms of renewable materials-based insulation development, innovation, and production are non-existent (expanded polystyrene and mineral being the predominantly used materials). Stringent new energy efficiency rules in construction and energy efficiency renovations are on the forefront of spending in the construction sector. Producers should develop complete solutions, not only replacement materials.

· There is no tradition of multi-storey wooden construction in Slovenia (and South-East Europe, in general). Furthermore, much of southern Europe is earthquake prone, which requires adequate consideration in wooden construction solutions.

· Mobile home manufacturing and container-based mobile living units are a strong sector in Slovenia. However, renewable materials are not, or are only scarcely used in their production.

Opportunities:

· The public is increasingly aware of the necessity for and advantages of sustainable construction. However, there are no known attempts to introduce Restorative Environmental Ergonomic Design (REED) principles to enhance general trends in sustainable construction.

· There were quite a few excellent research, development, pilot, and demonstration projects in the European Research Area (ERA) that successfully concluded in the past 5-10 years. Initial knowledge,

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materials, and building/renovation systems, therefore, exist and can be built upon for a significant shift towards renovations using renewable materials.

· There is a strong political backing for wooden construction. One of the main tools for implementation is supposed to be Green Public Procurement.

· In the world of climate change, natural, and man-made disasters, there is ever-growing need for mobile, energy, and other infrastructure-independent living units. Combining innovation in wood industry/construction with industrial experience in mobile home production, there is a viable opportunity for the sector, and its related value chains.

· Further development of the already strong prefab housing sector in Slovenia and sustainability certification of buildings (e.g., DGNB, BREEAM) must be realised.

· Slovenia and southern Europe must begin using CLT to construct multi-story wooden buildings and catch up with other countries like Austria, Sweden, Norway, and Finland.

· Development of innovative compositions of building kits, including the usage of new materials, has great potential in Slovenia and southern Europe.

REFERENCESInnoRenew CoE (2016) http://innorenew.eu/en/ (Accessed on January 25th, 2016)

ACKNOWLEDGMENTS

The authors thank all of the InnoRenew partners for their participation and support as well as the European Commission for funding the project under the Horizon2020 Widespread-2015 program.

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REEDCOB - AN ECO - EFFICIENT BUILDING TECHNOLOGY FOR MONOLITHIC WALLS BASED ON EARTH AND REEDSPaulina Faria1, Paulo Carneiro2, Alina Jerónimo2, Davide Malheiro1

1 NOVA University of Lisbon, 2829-516, Caparica and CERIS – Civil Engineering Research and Innovation for Sustainability, Univ. Lisboa, 1049-001 Lisboa, Portugal.

2 Architecture Professionals, Rua Marcos Marreiros 21, R/C, 1200-254 Lisboa, Portugal.

1paulina.faria@fct.unl.pt,1d.malheiro@campus.fct.unl.pt,2paulofmcf@gmail.com,2alinamjf@gmail.com

KEYWORDSeco-efficiency, monolithic wall, earth, reed, monitoring

New dwellings are needed all over the world. In developing countries new construction adopts modern materials such as fired bricks and cement concrete, consuming a large amount of energy for production of these building elements. Because of its apparent durability modern technology has been replacing ancient technology and causing a loss in vernacular knowledge still established in developing countries.

Trying to present alternatives to the previously mentioned status and also to define a technology that would give the possibility for unskilled craftsmanship to build easily and quickly, in a direct collaboration with FRADICAL company, it was decided to study an ecological and cost-controlled building technology for walls that can combine the use of materials that have been used in vernacular buildings all over the world, such as earth and air lime, with others also with low carbon footprint, as giant reeds in the form of cane and its fibres. Giant reed cane (Arundo Donax) is an invasive species in southern Europe which exists in excess in Portugal and in other countries. The aim is to develop a building technology capable of improving ancient vernacular knowledge but adapted to present time constraints and comfort needs.

A new technology for walls named “reedcob” was developed and has been characterized, namely by the building and monitoring of a prototype. The technology, based on cob walls, mainly consists on building monolithic walls but with successive layers of a mix based on earth and reed fibres, with low amounts of lime putty and pozzolan from ceramic waste, and layers of reeds.

The mix was optimised by using the following volumes: 1 of earth, 0.09 of lime putty, 0.06 of pozzolan and 1 of reed fibres. Therefore, the material of the walls is more than 50% from reed and the monolithic walls are lightweight compared to cob or rammed earth walls. Furthermore they do not need compaction as the previously mentioned techniques. Samples were produced and tested mechanically and physically. The building technology itself was applied to build a prototype cabin 18 m3. Five unskilled people - two architects and three civil engineering students – prepared the building materials, produced the mix and built the cabin walls in the Caparica Campus of NOVA University of Lisbon, 1 km from the Atlantic Ocean. A 40 cm thick wall foundation with stones and low cement-content concrete was built. Four wood pillars 7 cm x 7 cm section was previously inserted in the corners of the cabin walls foundation, at middle thickness, to increase bracing (Fig. 1). Supplementary low section wood pillars were placed in the lateral faces of the walls foundation to assure verticality during the building of the walls (fig. 1). Successive layers of the earth-reed fibres mix and

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layers of reeds (placed side by side) were applied to build the wall (fig.1). In the corners each layers of reeds were placed alternately in perpendicular directions, also to increase bracing. After four days, by the end July 2014, 2 m high walls were completed, and the lateral wood pillars were disassembled. The construction of the cabin has shown that the technology was easy and fast to use by unskilled craftsmanship. In September 2014 a thermal insulated roof and a door completed the cabin.

Figure 1: Reedcob cabin under construction showing: left - a reed layer, the bracing wood pillars in corner and the lateral pillars for verticality; right – a general view of the team

The cabin exterior surface has not been rendered (nor was the interior plastered), being exposed to weather conditions, namely rain and strong South wind (from the Atlantic). Only the South and West facades were lime washed. For the past 1.5 years the cabin has been monitored visually and continues to perform well; it has also been tested by non destructive techniques and exterior and interior temperature and relative humidity have been registered. Comparison to more common walls, based on earth as cob or rammed earth or concrete, has been made and results highlighted.

This new technology was developed to be used mainly in new construction in Europe, where giant reed is an invasive species, but it is foreseen that, in other Continents, the reed cane can be replaced by other types of reeds or bamboo.

REFERENCESCarneiro P., Jerónimo A., Silva V., Cartaxo F., Faria P. 2015. Improving building technologies with a sustainable strategy. Urban Planning and Architectural Design for Sustainable Development, Part 2, Naselli, Pollice, Amer (Eds.), Universitá del Salento, Italy: 376-387

ACKNOWLEDGMENTS

To FRADICAL company and particularly to Eng. Fernando Cartaxo.

DESIGNING WITH BIO-BASED BUILDING MATERIALS

– CHALLENGES AND OPPORTUNITIES - Madrid, Spain – 24th & 25th February 2016

COST ACTION FP1303 PERFORMANCE OF BIO-BASED BUILDING MATERIALSBOOK OF ABSTRACT FROM JOINT TECHNICAL WORKSHOP